PHP Presentation

Faculty : Diploma Engineering
Branch : Computer Engineering
Subject Name: PHP & MySQL
Subject Code : 360701
Author :
Amit K. Lakhani
Lecturer in Computer Engineering Department
Tolani Foundation Gandhidham Polytechnic
Adipur

Chapter - 1
Introduction to
PHP

1.Introduction to PHP
This unit covers…

1.1 History of PHP, Apache web server, MySQL & Open
source
1.2 Relationship between Apache, MySQL and PHP
(AMP module)
1.3 PHP configurations in PHP
1.4 Apache web server

Developed By: Amit Lakhani, TFGP Adipur

1.1
History of PHP, Apache
web server, MySQL &
Open source

History of PHP
• PHP is a general-purpose server-side scripting language
originally designed for Web development to produce
dynamic Web pages.
• It is one of the first developed server-side scripting
languages to be embedded into an HTML source
document, rather than calling an external file to process
data.
• Ultimately, the code is interpreted by a Web server with a
PHP processor module which generates the resulting Web
page. It also has evolved to include a command-line
interface capability and can be used in standalone
graphical applications.


History of PHP conti..
• PHP can be deployed on most Web servers and also as a
standalone shell on almost every operating system and
platform free of charge.
• PHP was originally created by Rasmus Lerdorf in 1995.
The main implementation of PHP is now produced by The
PHP Group and serves as the formal reference to the PHP
language.
• PHP is free software released under the PHP License,
which is incompatible with the GNU General Public
License (GPL) due to restrictions on the usage of the term
PHP.
• While PHP originally stood for "Personal Home Page", it is
now said to stand for "PHP: Hypertext Preprocessor", a
recursive acronym. Developed By: Amit Lakhani, TFGP Adipur

History of MySQL
• MySQL is the world's most used relational database
management system (RDBMS) that runs as a server
providing multi-user access to a number of databases.
• It is named after developer Michael WideniusThe SQL
phrase stands for Structured Query Language.
• The open source database product that puts the "M" in
LAMP, was created by MySQL AB, a company founded in
1995 in Sweden. In 2008, MySQL AB announced that it
had agreed to be acquired by Sun Microsystems for
approximately $1 billion.


History of Apache web server
• The Apache Web Server Foundation was created in late
February, 1994 by a team of eight core contributors, and
three additional contributors. The first release was made
in April, 1995.
• The Apache Web (HTTP) Server is designed to provide
static and dynamic web pages over the Internet. It is used
by large enterprises, to students to home users for
everything from mission critical applications to simple
one page websites. Apache is the web server component
of the popular LAMP (Linux, Apache, MySQL,Perl/Python
/ PHP) application stack.


History of Apache web server conti..
• The web server is software that allows a computer to
host web pages. The most popular Apache is a web
server, an open source which runs on Windows, Linux
and other operating systems.
• The web server lets you write and test programs running
from your local computer exactly the same way they will
be seen on the internet.
• Apache doesn’t serve up just HTML files it handles a wide
range of files, from images and flash files to MP3 audio
files, RSS feeds and so on.


Open source
• Refers to a program or software in which the source code
(the form of the program when a programmer writes a
program in a particular programming language) is
available to the general public for use and/or
modification from its original design free of charge.

• Open source code is typically created as a collaborative
effort in which programmers improve upon the code and
share the changes within the community.


Open source conti..
• The basics behind the Open Source Initiative is that when
programmers can read, redistribute and modify the
source code for a piece of software, the software
evolves. Open source sprouted in the technological
community as a response to proprietary software owned
by corporations.


1.2
Relationship between
Apache, MySQL and
PHP

Relationship Apache, MySQL and PHP

• AMP stands for Apache web server, MySQL database
and PHP or Perl or Python language.
• PHP is used to create web pages, MySQL is used to create
database for the storage and Apache is used to run PHP
pages.
• The combination of these three allows us to create
dynamic and interactive websites.
• It can be used on cross platforms means we can install it
on WINDOWS (WAMP) or on LINUX (LAMP).


1.3
PHP configurations in
IIS


PHP configuration in IIS
Configuration of PHP on IIS includes following steps. This
guide provides configuration about IIS 5.1 shipped with
Window XP sp2.
1- Download latest version of PHP from
http://www.php.net/downloads.php. Note you should
download installer version not the zip version. Installer
version automatically performs all necessary
configurations. If we use zip version, Environmental
variables must be modified manually
2- Run the setup and choose installation directory for
example C:PHP
3- On next screen choose your version of web server, here
choose IIS ISAPI and click next.

PHP configuration in IIS conti..
4- On next screen in the extension portion choose
extensions to be installed on local hard drive and click
Install. You may add and remove extension later.


Installing WAMP on WINDOWS
Run the installer file.


Installing WAMP on WINDOWS conti..
In the license agreement click [I accept the agreement],
then click next.


Select the directory where you would like to install
WAMP.


Select the start menu folder where you would like to
place WAMP’s shortcuts.


In the additional tasks you may select if WAMP would be
loaded on startup or no.


This is the confirmation screen of the options you have
selected. Click back to modify your install settings or click
next to start the installation.


Some time midway into the installation a window will
pop-up asking for the directory where to save the
document root folder. It is recommended that you leave it
as it is and click ok to continue the installation.


After the said pop-up another window will appear asking
for you default browser. If you have no preference for
browsers just hit Open. If not search for the .exe file of
your preferred browser then click Open to continue the
installation.


Once the installation is finished, click finish.


In your System Tray you should now see a “WAMP” icon.
Click it, and select Put Online (Note: if it says Put Offline
ignore this step and skip to the next one).


1.4
Apache Web server


Apache webserver
• Apache is generally recognized as the world's most popular
Web server (HTTP server). Originally designed for Unix
environments, the Apache Web server has been ported to
Windows and other network operating systems.

• The name "Apache" derives from the word "patchy" that
the Apache developers used to describe early versions of
their software.

•The Apache Web server provides a full range of Web server
features, including CGI, SSL, and virtual domains.


Apache webserver conti..
• Apache also supports plug-in modules for extensibility.
Apache is free software, distributed by the Apache
Software Foundation that promotes various free and open
source advanced Web technologies.
Configuration Files
• Apache uses a system of three text files for managing its
configuration data. All three of these files (almost always)
appear in Apache's ./conf directory and are designed to be
edited by system administrators:
httpd.conf for general settings
srm.conf for resource settings
access.conf for security settings



• When Apache first starts, these files are processed in the
order shown above. Originally, the initial installation of
Apache included default entries within each of the three
files.
• In the most recent versions of Apache, however, the
default installation has changed. Now httpd.conf is treated
as the "master" configuration file and it contains all of the
settings. Both srm.conf and access.conf still exist in the
installation, but they contain no settings and are empty
except for some comments.


• Like many UNIX-style programs, Apache will not re-read
the .conf files after the Web server starts running. After
making changes, an administrator must restart Apache for
the new settings to take effect.

Inside Httpd.conf
• Traditionaly httpd.conf contained general settings such as
the ServerName and Port number. These entries appear
as follows in the file:
ServerName localhost
Port 80


• The term "httpd" stands for HTTP Daemon. Recall that
in a UNIX environment, the term daemon refers to a type
of process designed to launch at system boot and continue
running for very long periods of time. The name doesn't
make much sense on a Windows platform, but the concept
of a UNIX daemon can be compared to the concept of
Windows services.
• The Windows port of Apache allows for installation as a
Windows service but does not require it. This file contains
a number of other entries (technically called directives),
but for most of these, modifications are optional.


• Probably the most useful of these entries is ServerAdmin –
it allows the administrator to set the email address that
will be displayed on error pages (such a "404 pages") in the
client's browser, giving users a way to contact someone if a
site problem occurs:
ServerAdmin compnetworking.guide@about.com
Access and Security Settings
• It is recommended practice now for Apache administrators
to manage their resource and security settings from
httpd.conf. Administrators of older versions of Apache can
simply cut their entries from srm.conf and access.conf and
paste them into the master file.

• If an administrator wants to go one step further and
delete the two empty files, they should also place the
following entries in httpd.conf to prevent Apache from
attempting to access them:
AccessConfig /dev/null
ResourceConfig /dev/null Conclusion
• The family of .conf files supports most but not all of
Apache's configuration options. Other important
mechanisms for managing an Apache Web server include
the .htaccess file, the mime.types file, and the family of log
files. Look for discussion of these in a future article.


Summary

• History of PHP, Apache web server, MySQL & Open
source
• Relationship between Apache, MySQL and PHP
(AMP module)
• PHP configurations in PHP
• Apache web server


Chapter - 2

Basics of PHP

2.Basics of PHP
This unit covers…
2.1 PHP Structure and syntax
2.2 Creating the PHP pages
2.3 Rules for PHP syntax
2.4 Integrating HTML with PHP
2.5 Constants, Variable: static and global variable
2.6 Conditional structure and looping
2.7 PHP operator
2.8 Arrays foreach construct
2.9 User defined function, argument function, variable
function, return function, default argument, variable
length argument

2.1
PHP structure and
syntax


PHP structure and Syntax

PHP is a scripting language commonly used on web
servers.

• Stands for “PHP: Hypertext Preprocessor”
• Open source
• Embedded code
• Comparable with ASP
• Multiple operating systems/web servers


What can it do?

• Dynamic generation of web-page
content
• Database interaction
• Processing of user supplied data
• Email
• File handling
• Text processing
• Network interaction
• And more…


Fundamentals

• PHP is embedded within xhtml pages within the tags:
<?php … ?>

• The short version of these tags can also be used: <? …
?>

• Each line of PHP is terminated, like MySQL, with a semi-
colon.


2.2
Creating the PHP pages


2.2 Creating the PHP pages

<html>
<head>
<title>PHP Test</title>
PHP statement
</head>
<body>
<?php echo ‘<p>Hello World!</p>’; ?>
</body>
</html>


2.3
Rules for PHP syntax


Rules for PHP syntax
•Just as with other programming languages, in PHP, you
can create variables and process them in different in
different ways.

• With PHP, variable names are preceded with a dollar
sign, such as $amount. The variable name itself (after
the $) can start with a letter or underscore, and then
followed by any sequence of letters, digits, or
underscores. (That’s like most languages – variables can
have letters, digits, and underscores, but can’t start with
a digit.) And technically, the dollar sign isn’t part of the
variable name.

Rules for PHP syntax conti..
• The semicolon signifies the end of a PHP statement and
should never be forgotten. we would need to place a
semicolon at the end of each statement.

• As with HTML, whitespace is ignored between PHP s
tatements. This means it is OK to have one line of PHP
code, then 20 lines of blank space before the next line of
PHP code. You can also press tab to indent your code
and the PHP interpreter will ignore those spaces as
well.


Literals..

• All strings must be enclosed in single of double
quotes: ‘Hello’ or “Hello”.

• Numbers are not in enclosed in quotes: 1 or 45
or 34.564

• Booleans (true/flase) can be written directly as
true or false.


Comments

// This is a comment
# This is also a comment
/* This is a comment
that is spread over
multiple lines */

Do not nest multi-line comments
// recommended over #


Displaying Data
• There are two language constructs available
to display data: print() and echo().
• They can be used with or without brackets.
• Note that the data ‘displayed’ by PHP is actually
parsed by your browser as HTML. View source
to see actual output.
<?php
echo ‘Hello World!<br />’;
echo(‘Hello World!<br />’);
print ‘Hello World!<br />’;
print(‘Hello World!<br />’);
?>

Escaping Characters
• Some characters are considered ‘special’

• Escape these with a backslash

• Special characters will be flagged when they
arise, for example a double or single quote
belong in this group…

<?php
echo ‘Claire O’Reilly ’;
echo “said ”Hello”.”;
?>

Variables: What are they?
When we work in PHP, we often need a labelled place to
store a value (be it a string, number, whatever) so we can
use it in multiple places in our script.
These labelled ‘places’ are called VARIABLES
Variable naming Rules:
• $ followed by variable name
• Case sensitive
• $variable differs from $Variable
• Stick to lower-case to be sure!
• Name must started with a letter or an underscore
• Followed by any number of letters, numbers
and underscores


Variables: example

<?php
$name = ‘Phil’;
$age = 23;
echo $name;
echo ’ is ‘;
echo $age;
// Phil is 23
?>


2.4
Integrating HTML with
PHP


integrating HTML with PHP

<html>
<head>
<title>PHP Test</title>
PHP statement
</head>
<body>
<?php echo ‘<p>Hello World!</p>’; ?>
</body>
</html>


2.5
Constant variable:
constant and global
variable

Constant variable
• Constants (unchangeable variables) can also be
defined.
• Each constant is given a name (note no
preceding dollar is applied here).
• By convention, constant names are usually in
UPPERCASE.

<?php
define(‘NAME’,‘Phil’);
define(‘AGE’,23);
echo NAME;
echo ’ is ‘;
echo AGE;
// Phil is 23
?> Developed By: Amit Lakhani, TFGP Adipur

2.6
Conditional
Structure and
Looping

Control Structures

• if, elseif, else
• while, do … while
• for, foreach
• switch
• break, continue, return
• require, include, require_once, include_once


If statement

• To do something depending on a
comparison, use an if statement.
if (comparison) {
expressions; // do if TRUE
}
• NB: Notice the curly brackets – these are
important!


If example

<?php
$a = 10;
$b = 13;
if ($a<$b)
{
echo ‘a is smaller than b’;
}
?>


Extending IF statements

• It is possible to add extra optional clauses to
if statements..
if (comparison) {
expressions; // do if TRUE
} else {
expressions; // do otherwise
}


Extending If statements example
if (comparison1)
{
expressions;
}
elseif (comparison2)
{
expressions;
} else
{
expressions;
}


An example..

$a = 10;
$b = 13;
if ($a<$b) {
echo ‘a is smaller than b’;
} elseif ($a==$b) {
echo ‘a is equal to b’;
} else {
echo ‘a is bigger than b’;
}


While loops

• Might want to do something repeatedly while a
comparison is true..

while (comparison)
{
expressions;
}


While loop example

• Lets count to 10! Displays 1,2,3,4,5,..,10:

$i = 1;
while ($i <= 10)
{
echo $i++;
}


Do .. While

An alternative...

$i = 1;
do {
echo $i++;
}
while ($i <= 10);


For loop

Sometimes we want to loop around the same bit of
code a number of times.. Use a for loop.

for (expr1; expr2; expr3) { statements; }
• expr1 evaluated/executed initially
• expr2 evaluated at beginning of each
iteration (Continues if TRUE)
• expr3 evaluated/executed at end of each
iteration


For loop example

To count from 1 to 10:
Continue if true
initialise Execute at end of loop

for ($i=1; $i<=10; $i++)
{
echo $i;
}


Foreach loop

A foreach loop is designed for arrays. Often you want
to loop through each item in an array in turn..

$letters = array(‘a’,’b’,’c’);
foreach ($letters as $value)
{
echo $value;
} // outputs a,b,c in turn


Foreach.. With keys

Sometimes we want to use the array ‘key’ value too:

$letters = array(‘a’,’b’,’c’);
foreach ($letters as $key => $value)
{
echo “array $key to $value”;
}


Switch statement
• expr is evaluated switch (expr)
– Case corresponding {
to result is executed case (result1):
– Otherwise default statements;
case is executed break;
• break case (result2):
– Ensures next case statements;
isn’t executed
break;
default:
statements;
}

Switch Example
switch ($name)
{
case ‘Rob’:
echo ‘Your name is Rob’;
break;
case ‘Fred’:
echo ‘You are called Fred’;
break;
default:
echo ‘Not sure what your name is’;
}


break, continue, return
• break
• Ends execution of current for, foreach, do …
while, while or switch structure
• Option: Number of nested structures to break
out of
• continue
• Skip rest of current loop
• Option: Number of nested loops to skip
• return
• Ends execution of current function/
statement / script


2.7
PHP operators


Expressions
• Using variables within expressions to do
something is what PHP is all about.

<?php
$name = ‘Rob’;
echo $name;
?>


Operators in PHP
• Arithmetic
• Assignment
• Bitwise
• Comparison
• Ternary
• Incrementing
/decrementing
• Logical
• String


String Operators

Use a dot to concatenate two strings:

e.g.
$firstname = ‘Rob’;
$surname = ‘Tuley’;
// displays ‘Rob Tuley’
echo $firstname.’ ‘.$surname;


Arithmatic Operators

Example Name Result

$a + $b Addition Sum of $a and $b.

$a - $b Subtraction Difference of $a and $b.

$a * $b Multiplication Product of $a and $b.

$a / $b Division Quotient of $a and $b.

$a % $b Modulus Remainder of $a divided by
$b.


Assignment Operators

Example Result

$a = $b Sets $b to the same value as
$a.

$a += $b Equivalent to $a = $a + $b.

$a .= $b Equivalent to $a = $a.$b.


Combining Operators

Note that you can combine operators, for example use
=, + and / in one expression:

$a = 4;
$b = 2;
$c = $a + $b + ($a/$b);
// $c has value 4+2+(4/2) = 8

Brackets help group operators.


Comparison Operators
Example Name Result
$a == $b Equal TRUE if $a is equal to $b.
$a != $b Not equal TRUE if $a is not equal to $b.
$a <> $b Not equal TRUE if $a is not equal to $b.
$a < $b Less than TRUE if $a is strictly less than
$b.
$a > $b Greater than TRUE if $a is strictly greater
than $b.
$a <= $b Less than or equal TRUE if $a is less than or equal
to to $b.
$a >= $b Gtr than or equal TRUE if $a is greater than or
to equal to $b.

Comparisons operator example

• Comparison expressions return a value of
TRUE (or ‘1’) or FALSE (or ‘0’).
e.g.
$a = 10;
$b = 13;
// result is true (‘1’)
echo $a < $b;


Incrementing/Decrementing
Example Name Effect
++$a Pre- Increments $a by one, then
increment returns $a.
$a++ Post- Returns $a, then increments $a
increment by one.
--$a Pre- Decrements $a by one, then
decrement returns $a.
$a-- Post- Returns $a, then decrements
decrement $a by one.


Logical Operators

Example Name Result
$a and $b And TRUE if both $a and $b are TRUE.
$a or $b Or TRUE if either $a or $b is TRUE.
$a xor $b Xor TRUE if either $a or $b is TRUE, but not both.
!$a Not TRUE if $a is not TRUE.
$a && $b And TRUE if both $a and $b are TRUE.
$a || $b Or TRUE if either $a or $b is TRUE.


Ternary Operators

A single ? is the ternary operator.
(expr) ? if_expr_true :
if_expr_false;
A test expression evaluates to TRUE or FALSE.
TRUE gives first result (before colon)
FALSE gives second result (after colon)


Ternary Operators example
<?php
$a = 10;
$b = 13;
echo $a<$b ? ‘a smaller’:‘b smaller’;
// string ‘a smaller’ is echoed
// to the browser..
?>


2.8
Arrays


Array

• So far, we have stored ONE piece of data in each
variable.

• It is also possible to store multiple pieces of data in
ONE variable by using an array.

• Each piece of data in an array has a key..


Working with Array

• Note that trying to echo an entire array will not
display the data. To print an entire array to screen (for
debug, for example) use the function print_r instead.

print_r($letters);


Array example

Normal Variable, no key:
$name = ‘Rob’;
Array Variable, multiple pieces with ‘keys’:
$name[0] = ‘Rob’;
$name[1] = ‘Si’;
$name[2] = ‘Sarah’;
…
The ‘key’


Array key

• Array keys can be strings as well as numbers..
Array key

$surname[‘rob’] = ‘Tuley’;
$surname[‘si’] = ‘Lewis’;

• Notice the way that the key is specified, in square
brackets following the variable name.


Types of Array
• Indexed / Numeric array
• Indexed array have keys automatically assigned,
starting from 0.
• Values are stored and accessed in linear fashion
• Associative array
• Use keys that are manually specified and they
use string as index.
• A key is some string value
• Stores element values in association with key
values rather than in linear indexed order.


Indexed / Numeric Array
• This array can store numbers, sting and objects but
their index represented by numbers and starts from
0.
//first method to create array by array() function
<?php
$varArray= array(1,2,3,4);
?>
//second method to create array
<?php
$varArray[0]= 1
$varArray[1]= 2
$varArray[2]= 3
?>

Example of Indexed / Numeric Array
<?php
//first method to create array
Output:
$varArray= array(1,2,3,4,5);
foreach($varArray as $val)
{
print_r($val);
}
//second method to create array
$varArray[0]= 1
$varArray[1]= 2
$varArray[2]= 3
print_r($val);

Associative Array
• associative will have their index as string so that
you can establish strong association between key
and value.
Array key Array value

<?php
$dept['comp'] = "32";
$dept['it'] = "30";
$dept['ec'] = "34";
print_r($dept['it']);
?>


Example of Associative Array
// first method to create array
<?php
Output:
$dept['comp'] = "32";
$dept['it'] = "30";
$dept['ec'] = "34";
?>
// second method to create array
<?php
$dept=array(“comp” => 32,
“it” => 30,
“ec” => 34,
?>

Adding an element
to Arrays


Adding an element to an Array

• Adding an element to indexed array using [ ] operator
and array_push() function

• Adding an element to an associative array by specifying
index

• Adding an element to to the beginning of an array using
array_unshift() function.


Adding an element to an Array example
• You can add automatically indexed element using [ ]
operator
<?php
$varArray=array(); Add an element to array
$varArray[]=1;
$varArray[]=2;
for($i=0;$i<=1;$i++) Output:
{
echo $varArray[$i];
}
$varArray=array();
array_push($varArray, 10,20);
for($i=0;$i<=1;$i++)
{
echo $varArray[$i];
}?> Developed By: Amit Lakhani, TFGP Adipur

Adding an element to an Associative array
• You can specify the index when adding an element.

<?php Add an element to array
$varArray=array();
$varArray['one']=1;
$varArray['two']=2;
echo $varArray['one'];
?>

Output:


Adding an element using array_unshift()
• You can add an element to the beginning of an array
using array_unshift() function.
<?php
Output:
varArray=array('three');
array_unshift($varArray, 'one');
array_unshift($varArray, 'two');
array_unshift($varArray, 'three');
print_r("$varArray[0]");
print_r("$varArray[1]");
print_r("$varArray[2]"); Add an element to array
?>


Removing an
element from Arrays


Removing an element from array

• You can remove an element using unset() function

• You can remove the last element of an array using
array_pop() function

• You can remove the first element of an array using
array_shift() function


Removing an element from array conti..
• You can remove an element using unset() function
<?php
$varArray=array(); Output:
$varArray[]=1;
$varArray[]=2;
for($i=0;$i<=1;$i++)
{
echo $varArray[$i];
}
unset($varArray[0]);
for($i=0;$i<=1;$i++)
{ Unset the first element
echo $varArray[$i]; Of an array
}?>

• You can remove last element using array_pop() function
<?php
$varArray[]=1;
$varArray[]=2;
for($i=0;$i<=1;$i++)
{
echo $varArray[$i];
}
$last=array_pop($varArray);
for($i=0;$i<=1;$i++) Remove last element
{ Of an array
echo $varArray[$i];

• You can remove first element using array_shift() function
<?php
$varArray[]=1;
$varArray[]=2;
for($i=0;$i<=1;$i++)
{
echo $varArray[$i];
}
$first=array_shift($varArray);
for($i=0;$i<=1;$i++) Remove first element
{ Of an array
echo $varArray[$i];

Counting and
combining elements
of Arrays


Counting element of array
• You can determine the sizeof an array using count() function
<?php
$varArray=array(1,2,3,4,5);
$varArray_1=array();

echo "The number of elements in first the no of
Counts
array=".count($varArray); elements in array

echo "The number of elements in second
array=".count($varArray_1);
?>
Output:


Combining multiple array
• You can combine multiple array using array_merge() function

<?php
$varArray_1=array(6,7,8,9);

$arr_merge = array_merge($varArray, $varArray_1);

print_r($arr_merge);
Combines
?> Elements of array
Output:


Searching Array


Searching arrays
• You can see an element with a certain key exists using
array_key_exists() function

isset() function

• You can check if a specific element exists in an array
using in_array() function.


Searching arrays conti..
array_key_exists() function

<?php key Array name
$varArray[0]=1;
$varArray[1]=2;
if(array_key_exists(1,$varArray))
{
print_r($varArray[1]);
}
?> Output:


isset() function

<?php Array name
$varArray['one']=1;
$varArray['two']=2;
if(isset($varArray['one']))
{
print_r($varArray['one']);
}
?>
Output:


• You can check if a specific element exists in an array
using in_array() function.

<?php key Array name
echo"<font size=50>";
$varArray['0']=1;
$varArray['1']=2; Output:
if(in_array(1,$varArray))
{
}
?>

Sorting Array


Sorting arrays
• PHP has a rich collection of sorting functions
that allow you to sort by values and keys.

• Variants on most of these functions facilitate
sorting in forward or reverse order and provide
you with the option of preserving or resetting
the associations between array keys and values.

• All of PHP’s array sorting functions work on
arrays in place and return TRUE to indicates
success or FALSE in the event of failure.


Sorting arrays conti..
• Sorting an Array by Its Values using sort()

• Sorting an Array by Its Values using asort()

• Sorting an Array by Its Keys using ksort()

• Reversing an Array Using arsort()

• Reversing an Array Using krsort()

• Reversing an Array Using array_reverse()


• Sorting an Array by Its Values using sort():
To order an array’s elements using their values, use
the sort() function. This function takes as its arguments
the array to be sorted and an optional sort flag, and, like
PHP’s other sorting functions, this one sorts the array in
place.
<?php
print_r($varArray);
sort($varArray);
print_r($varArray); Sort an array
?>

• Sorting an Array by Its Values using asort():
Because sort() resets all the indexes, you have lost
the original keys. To get around this issue, you can use the
asort() function instead. This works in the same way as
sort() except in one respect: it preserves the array’s
original key/value associations.

<?php
$varArray['one']= "second";
$varArray['two']= "first";
$varArray['three']= "third";
asort($varArray); Sort an array
print_r($varArray);

• Sorting an Array by Its Keys using ksort():
Particularly with regard to associative arrays, it is
just as important to be able to sort arrays by their keys as
it is by their values. The ksort() function accomplishes this
while maintaining the relationship between keys and
values.
<?php
$varArray['one']= "second";
$varArray['two']= "first";
$varArray['three']= "third";
ksort($varArray); Sort an array
By its keys
print_r($varArray);
?>

• Reversing an Array Using arsort():
To sort an associative array by value in reverse
order, use arsort(). Like asort(), this function preserves the
array’s keys.

<?php
$varArray_1['one']= "second";
$varArray_1['two']= "first";
$varArray_1['three']= "third";
arsort($varArray_1); Sort an array
In reverse order
print_r($varArray_1);
?>


• Reversing an Array Using krsort():
The krsort() function sorts an array by key in reverse order.

<?php
krsort($varArray_1); Sort an array
In reverse order
?>


• Reversing an Array Using array_reverse()
The array_reverse() function does just what you
would expect; it reverses the order in which the elements
of an array are listed.

<?php
array_reverse($varArray_1);
?> Sort an array
In reverse order

Sorting arrays example


Looping over arrays
• The easiest way to loop over is foreach()
• Each element in foreach() is a copy. i.e modifying the
elements has no effect on the original array.

<?php
$varArray= array(1,2,3,4,5);
print_r($varArray);
{
print_r("$val");
echo"<br>";
}
?>

Array operators
Example Name Result
$a + $b Union Union of $a and $b.
$a==$b Equality TRUE if $a and $b have the
same key/value pairs
$a===$b Identity TRUE if $a and $b have the
same key/value pairs in the
same order of the same type.
$a!=$b Inequality TRUE if $a is not equal to $b
$a<>$b Inequality TRUE if $a is not equal to $b
$a!==$b Non-identity TRUE if $a is not identical to $b


2.9
User defined function, argument
function, variable function,
return function, default
argument, variable length
argument

Functions
• User defined functions

• Argument functions

• Variable functions

• Return functions

• Default argument

• Variable length argument


User defined functions
• Functions are defined using the keyword function
by the function name
• Functions may have 0 or more arguments
• Code body appears between opening and closing
paranthesis.
• Functions name begins with a letter or
underscore, followed by any letter, numbers or
underscores.
• Function is called using the function name.
• Function do not need to be declared
• Recursion is supported


Example of User defined functions
<?php
function first()
{
echo "This is first function";
}
function sec()
{
print "this is second function";
}
first(); Output:
sec();
?>

Functions argument
• variables can be passed either by value of by reference
Function arguments
<?php
function addvalues ($value1 = 0, $value2 = 0, $value3 = 0)
{
$total = $value1 + $value2 + $value3;
return $total;
} Output:
echo addvalues (1) . "<br />";
echo addvalues () . "<br />";
echo addvalues (1,2,3);
?>


Variable length argument
• In addition to support default values for function
argument PHP supports variable length argument with
function such as func_get_args()

• Regardless of what the function definition dictates you
can retrieve every single value passed to function using
func_get_args()

• This functions returns an array where each element is
corresponds to a single argument.

• This is useful when you want function to accept any
number of arguments

Example of Variable length argument
<?php

function display($name)
{
foreach(func_get_args() as $arg)
{
echo $arg."<br>";
} Output:

}

display("computer","IT","EC");
?>


Returning values
• You can return a value from an array using the return
keyword.

• If there is no return executed then NULL is the default
value

• You can return only a single value from a function by
returning a more complex value such as an array or an
object which encapsulate multiple values and using by
reference arguments and update those value in your
function.


Example of Returning values
<?php
function addandsubtract ($firstvalue, $secondvalue)
{
$firstreturnvalue = ($firstvalue + $secondvalue);
$secondreturnvalue = ($firstvalue - $secondvalue);
$myarray = array ();
$myarray[0] = $firstreturnvalue;
$myarray[1] = $secondreturnvalue;
return $myarray;
}
$myarray = array ();
$myarray = addandsubtract (10, 3);
echo $myarray[0] . "<br />";
echo $myarray[1]; ?> Developed By: Amit Lakhani, TFGP Adipur

Object oriented
programming in PHP


Object oriented concepts
• Class: User defined data type which includes local
function as well as local data.
• Object: An individual instance of the data structure
defined by a class. They are also known as instance.
• Member variable: variables defined inside the class.
This data will be invisible to the outside of the class
and can be accessed by the member functions.
• Member Function: functions defined in the class
and are used to access object data.
• Inheritance: When a class is defined by inheriting
existing functions of a parent class then it is called
inheritance.

Object oriented concepts conti…
• Parent class: A class that is inherited by other class.
It is also known as base class or super class.
• Child class: A class that inherits the property of
other class(parent). It is also known as subclass or
derived class.
• Polymorphism: same function can be used for
different purposes.
• Overloading: A type of polymorphism in which
some or all of operators have different
implementation depending on the type of
arguments.
• Data abstraction: Data details are hidden.

Object oriented concepts conti…
• Encapsulation: where data and member functions
can be encapsulated together to form an object.
• Constructor: special type of function which will be
called automatically whenever there is an object
formation from a class.
• Destructor: special type of function which will be
called automatically whenever there is an object
deleted or goes out of scope.


What is a class?
Conceptually, a class represents an object, with
associated methods and variables
<?php
class sample $obj = new sample();
{ $obj->getvalue();
var $val; $obj->showvalue();
function getvalue() ?>
{
$this->val=10;
Output:
}
function showvalue()
{
echo "you have entered”.$this->val;
}}; Developed By: Amit Lakhani, TFGP Adipur

Constructor function
• Constructor functions are special types of function
which are called automatically whenever an object
is created.

• PHP provides a special functions called __construct()
to define a constructor, you can pass any number of
arguments.

• Remember.. if the constructor requires arguments,
they must be passed when it is instantiated!


Constructor function example
<?php
class sample $obj=new sample(100, "computer");
{ $obj->showvalue();
var $ID; ?>
var $name;
function __construct($ID, $name)
{ Output:
$this->ID= $ID;
$this->name = $name;
}
function showvalue()
{
echo "ID:".$this->ID."<br>";
echo "Name:".$this->name."<br>“;}}; TFGP Adipur
Developed By: Amit Lakhani,

Destructor function
• Like constructor function you can define a destructor
function using __destruct().
• You can release all the resources within destructor
<?php
$obj=new sample();
class sample
?>
{
function __construct() Output:
{
echo "The constructor is called ";
}
function __destruct()
{
echo "The destructor is called ";
}}; Developed By: Amit Lakhani, TFGP Adipur

Inheritance
• The real power of using classes is the property of
inheritance – creating a hierarchy of interlinked
classes.

Department
parent
children
Computer Mechanical


Inheritance conti…..
• The child classes ‘inherit’ all the methods and
variables of the parent class, and can add extra ones
of their own.

• The effect of inheritance is that the child class has the
following characteristics:

• Have all the member variable declarations of the parent
class.

• Have all the same member functions as the parent,
which will work the same way as those functions do in
the parent.

Inheritance example
class pclass class cclass extends pclass
{ Parent class {
child class
var $p_value; var $c_val;
function p_getval() function c_getval()
{ {
$this->p_value = "parent"; $this->c_val="child";
} }
function p_showval() function c_showval()
{ {
echo "This is $this->p_value class"; echo "This is $this->c_val class";
}} }}
$cobj= new cclass();
$cobj->p_getval(); Object creation
$cobj->p_showval();
$cobj->c_getval();
$cobj->c_showval();?> Developed By: Amit Lakhani, TFGP Adipur

Access specifier
• Public member:
• By default properties and methods are public.
• They may be accessed from outside of the class.
• They may be accessed from within the class.
• They may be accessed from within the class that
implements it in inheritance.

class sample
{
var $count;
}


Access specifier conti…
• Private member:
• By designing a member private, you limit the
accessibility to the class in which it is declared.
• The private member can’t be referred to from classes
that inherit the class in which it is declared and can’t
be accessed from outside of the class.
• A class member can be made private by using private
keyword in front of the member.

class sample
{
private $count;
}

Access specifier conti…
• Protected member:
• A protected property or method is accessible in the
class in which it is declared, as well as in classes that
extends that class.
• Protected members are not available outside of those
two classes.
• A class member can be made protected using
protected keyword in front of the member.

class sample
{
protected $count;
}

Interface


Interface concept
• You can think of an interface as a template that
tells you what methods a class should expose but
leaves the details up to you.

• Interfaces are useful in that they can help you
plan your classes without immediately getting
bogged down in the details.

• You can also use them to distill the essential
functionality from existing classes when it comes
time to update and extend an application.


Interface concept
• To declare an interface, simply use the
interface keyword, followed by the name
of the interface.

• Within the body of the interface, list
declarations (delimited, as with classes,
by braces, {...}) for any methods to be
defined by classes that implement the
Interface.


Interface example

<?php function p_showval()
interface show {
{ echo "This is” $this->p_value ;
function p_showval(); }
} }
class pclass implements show $cobj= new pclass();
{ $cobj->p_getval();
var $p_value; $cobj->p_showval();
function p_getval() ?>
{
$this->p_value = "parent";
Output:
}


Constants
• A constant is a variable which holds the value and
the value does not change.
•To declare a constant in a class, all you have to do
is precede an identifier with the const keyword.
• A class constant is always public and static, and for
this reason you cannot use the keywords public,
private, protected, or static when declaring one.
class sample
{
const count;
--------
---------
}

Abstract classes
• An abstract class is one that can’t be instantiated
only inherited.

• An abstract class is declared using abstract
keyword.

• When inheriting from an abstract class, all methods
marked abstract in the parent’s class declaration
must be defined by the child and these methods
must be defined with the same visibility.


Final keyword
• PHP 5 introduces the final keyword, which prevents
child classes from overriding a method by prefixing
the definition with final.
• If the class itself is being defined final then it can’t
be extended.
class sample
{
final public getval()
{
--------
---------
}
}

Summary
• PHP Structure and syntax
• Creating the PHP pages
• Rules for PHP syntax
• Integrating HTML with PHP
• Constants, Variable: static and global variable
• Conditional structure and looping
• PHP operator
• Arrays foreach construct
• User defined function, argument function, variable
function, return function, default argument, variable
length argument

Chapter - 3
Working with
functions

Working with functions
PHP offers several built in functions for day to day
uses in coding

3.1 Variable functions 3.4 Date functions

3.2 String functions 3.5 Array functions

3.3 Math functions 3.6 File functions


3.1
Variable functions


Variable functions
• Gettype(): get the type of variable

• Settype(): set the type of variable

• Isset(): determine if the variable is set and not NULL

• Unset(): unset a given variable

• Strval(): get string value of variable

• Floatval(): get float value of variable

• Intval(): get the integer value of variable

• Print_r(): prints human readable information about a variable

Gettype() function
• get the type of variable

• Syntax: string gettype($var)

• Returns the type of the variable

• Example:
<?php
$var=21; Output:

echo gettype($var);
?>

settype() function
• determine if a variable is set and is not NULL

•Syntax: bool settype($var)

• Returns TRUE on success otherwise false

• Example:
<?php
$var=21; Output:
settype($var, "string");
echo gettype($var);
?>

isset() function
• set the type of variable
• Syntax: bool isset($var, “type”)
• Returns TRUE on success otherwise false
<?php
$var=NULL;
if (isset($var)=="TRUE")
{ Output:
echo "var is set";
}
else
{
echo "var is not set";
}echo gettype($var);?> Lakhani, TFGP Adipur
Developed By: Amit

unset() function
• unset a given variable

• Syntax: void unset($var)

• Example:
<?php
$var="comp";
echo "before unset<br>" .$var;
echo gettype($var);
unset($var);
echo "after unset<br>".$var;
echo gettype($var);
?>

strval() function
• Get string value of a variable

• Syntax: strval ( mixed $var )

Example:

<?php
$var=25;
echo strval($var);
?>
Output:


floatval() function
• Get float value of a variable

• Syntax: floatval ( mixed $var )

Example:

<?php
$var=25;
echo floatval($var);
?>
Output:


intval() function
• Get integer value of a variable

• Syntax: intval ( mixed $var , [int base =10])

Example:

<?php Output:
echo intval(42);
echo "<br>";
echo intval(4.2);
?>


print_r() function
• Prints human readable information about variable

• Syntax: print_r ($var)

• Example:

<?php
$var=array(1,2,3,4,5);
echo print_r($var);
?>
Output:


Var_dump() function
• Displays structured information (type and vale)
about variable.

• Syntax: var_dump ($var)

Example:
<?php
Output:
$var=1;
$var2=40.50;
echo var_dump($var);
echo"<br>";
echo var_dump($var2);

3.2
String functions


String functions
• chr()- returns a one character string containing the character
specified by ASCII value.

• ord()- returns the ASCII value of the first character of string.

• strtolower()- returns string with characters converted to lowercase

• strtoupper()-returns string with characters converted to uppercase

• strlen() -returns the length of the string

• ltrim()-strip whitespace from the beginning of a string

• rtrim()-strip whitespace from the end of a string


String functions conti…
• trim()-strip whitespace from the beginning and end of a string

• substr() -returns part of a string

• strcmp()-compares two inputs and returns an integer.

• strcasecmp()-compares two inputs and returns an integer.

• strncasecmp()-case sensitive string comparison for first n
characters

• strpos() -find position of first occurrence of a string

• strrpos() -find position of last occurrence of a string


String functions conti…
• strstr() -find first occurrence of a string and is case sensitive

•stristr() - find first occurrence of a string inside another string
and is case sensitive

• str_replace() -replace all occurrences of the search string with
the replacement string.

• strrev() -reverse a string

• echo() -output one or more string

• print() -output a string


chr() function
• returns one character string by ASCII value

•Syntax: string chr($var)

• Example:

<?php
echo "The character value of of 52 is: ".chr(52);
?>
Output:


ord() function
ord() function
• returns ASCII value of the first character of string

•Syntax: int ord($string)

• Example:

<?php
echo ord("computer");
?>
Output:


strtolower() function
• returns string with characters converted to lowercase

•Syntax: string strtolower($str)

• Example:
<?php
echo "The output of string lower function:<br>";
echo strtolower("Computer DEPT.");
?>
Output:


strtoupper() function
• returns string with characters converted to uppercase

•Syntax: string strtoupper($str)

• Example:
<?php
echo "The output of string upper function:<br>";
echo strtoupper("Computer DEPT.");
?>
Output:


strlen() function
• returns the length of the string

•Syntax: int strlen($str)

• Example:
<?php
echo "The output of string length function:<br>";
echo strlen("Computer");
?>
Output:


ltrim() function
• strip whitespace from the beginning of a string
•Syntax: ltrim($str)
• Example:
<?php
echo "The output of ltrim function:<br>";
$str = " Computer department";
echo "Without ltrim: " . $str;
echo "The length is:". strlen($str);
echo "With ltrim: " . $str;
echo "The length is:". strlen(ltrim($str));
?>

rtrim() function
• strip whitespace from the end of a string

• Syntax: rtrim($str)
<?php
echo "The output of rtrim function:<br>";
$str = "Computer department ";
echo "Without rtrim: " . $str;
echo "The length of the string is:". strlen($str);
echo "With rtrim: " . $str;
echo "The length of the string is:". Strlen(rtrim($str));
?>


trim() function
• strip whitespace from the beginning and end of a string

• Syntax: string trim($str)
<?php
echo "The output of trim function:<br>";
$str = “ Computer department ";
echo "Without trim: " . $str;
echo "The length of the string is:". strlen($str);
echo "With trim: " . $str;
echo "The length of the string is:". Strlen(trim($str));
?>


substr() function
• returns part of a string

• Syntax: string substr($str, int $start, [int $length])

• Example:
<?php
echo "The output of substring function:<br>";
echo substr("Computer department!",3);
echo substr("Computer department!",3,5);
?>
Output:


strcmp() function
• compares two inputs and returns an integer.

• Syntax: int strcmp(string $str_1, string $str_2)

• Return values: returns < 0, if str_1 < str_2
returns > 0, if str_1 > str_2
returns 0, if str_1 = str_2
•Example:
<?php
echo "The output of string compare function:<br>";
echo strcmp("Computer","Computer");
?>

strcasecmp() function
• compares two inputs and returns an integer.

• Syntax: int strcasecmp(string $str_1, string $str_2)

•Example:
<?php
echo strcasecmp("Computer","COMPUTER");
?>

strncasecmp() function
• case sensitive string comparison for first n characters

• Syntax: int strncasecmp(string $str_1, string $str_2, int len)

•Example:
<?php
echo strncasecmp("Computer","COMPUTER“, 3);
?>

strpos() function
• find position of first occurrence of a string

• Syntax: int strpos(string $str, $needle, [ int $offset])

•Example:

<?php
echo "The output of string position function:<br>";
echo strpos("Computer","m“, 2);
?>
Output:


strrpos() function
• find position of last occurrence of a string

• Syntax: int strrpos(string $str, $needle, [ int $offset])

•Example:

<?php
echo "The output of string position function:<br>";
echo strrpos("Computer","m“, 2);
?>
Output:
The output of string position function:
2


strstr() function
• find first occurrence of a string and is case sensitive

• Syntax: strstr($str,search)

•Example:

<?php
echo "The output of strstr() function:<br>";
echo strstr("Computer","m“);
?>
Output:


stristr() function
• find first occurrence of a string inside another string
and is case sensitive

• Syntax: stristr($str,search)

•Example:
<?php
echo "The output of stristr() function:<br>";
echo stristr("Computer","m“);
?>


str_replace() function
• replace all occurrences of the search string with the
replacement string.

• Syntax: str_replace( find, replace, string, count )

•Example:
<?php
echo "The output of string replace function with case
sensitive: <br>";
echo str_replace("department","engg.","computer
department", $i);
echo $i;
?>

strrev() function
• reverse a string

• Syntax: strrev( $string)

•Example:

<?php
echo "The output of strrev() function: <br>";
echo strrev("computer department”);
?>
Output:


echo() function
• output one or more string

• Syntax: echo( $string)

•Example:

<?php
echo "The output of echo function<br>";
$i=1;
echo $i;
?>


print() function
• output a string

• Syntax: print( $string)

•Example:

<?php
print (“The output of print function<br>“);
$i=1;
print $i;
?>


3.3
Math functions


Maths function
• abs()-returns absolute value of a number

• ceil() -returns the value of a number rounded UPWARDS to the
nearest integer.

• floor()-returns the next lowest integer value by rounding down
value.

• round() -returns the rounded value to specified precision.

• fmod() -returns the floating point remainder of dividing the
dividend by the divisor.

•min() -returns smallest value

Maths function conti..

• max() -returns largest value

• pow() -returns base raised to the power of exp.

• sqrt() -returns the square root of the given number

• rand() -returns random value between min and max


abs() function
• returns absolute value of a number

•Syntax: abs(num)

• Example:

<?php
echo "The output of abs() function<br>";
echo(abs(6.99) . "<br />");
echo(abs(-3) . "<br />");
echo(abs(3));
?>


ceil() function
• returns the value of a number rounded UPWARDS to the
nearest integer.
• Syntax: float ceil(num)

• Example:

<?php
echo "The output of ceil() function<br>";
echo(ceil(0.60) . "<br />");
echo(ceil(0.40) . "<br />");
echo(ceil(5) . "<br />");
echo(ceil(5.1) . "<br />");
?>

floor() function
• returns the next lowest integer value by rounding down
value.
• Syntax: float floor(num)

• Example:

<?php
echo "The output of floor() function<br>";
echo(floor(0.60) . "<br />");
echo(floor(0.40) . "<br />");
echo(floor(5.1) . "<br />");
echo(floor(-5.1) . "<br />");
?>

round() function
• returns the rounded value to specified precision.

• Syntax: float round(num)

• Example:

<?php
echo "The output of round() function<br>";
echo(round(0.60) . "<br />");
echo(round(10.28765,2) . "<br />");
echo(round(-4.40) . "<br />");
echo(round(-4.60));
?>

fmod() function
• returns the floating point remainder of dividing the
dividend by the divisor.

• Syntax: float fmod($x,$y)

• Example:
<?php
echo "The output of fmod() function to
display remainder(modulo)<br>";
$r = fmod(5,2);
echo $r;
?>

min() function
• returns smallest value

• Syntax: min($val1, $val2,….)

• Example:

<?php
echo "The output of min() function <br>";
$r = min(5,2);
echo $r;
?>


max() function
• returns largest value

• Syntax: max($val1, $val2,….)

• Example:

<?php
echo "The output of max() function <br>";
echo(max(5,7) . "<br />");
echo(max(-3,5) . "<br />");
?>


pow() function
• returns base raised to the power of exp.

• Syntax: pow($base, $exp)

• Example:

<?php
echo "The output of pow() function <br>";
echo pow(4,2) . "<br />";
echo pow(6,2) . "<br />";
?>


sqrt() function
• returns the square root of the given number

• Syntax: float sqrt($arg)

• Example:

<?php
echo "The output of sqrt() function <br>";
echo(sqrt(1) . "<br />");
echo(sqrt(9) . "<br />");
?>


rand() function
• returns random value between min and max

• Syntax: int rand(void)
int rand($min, $max)

• Example:
<?php
echo "The output of rand() function <br>";
echo(rand() . "<br />");
echo(rand(10,100));
?>


3.4
Date functions


date() function
• Date() – format a local date/time

• Getdate() – get date time information

• Setdate() – sets the date

• Checkdate() – validates a date

• Time() – return current UNIX timestamp

• Mktime() – get the UNOX timestamp for a date


date() function
• returns a local time and date

•Syntax: string date($format, [int $timestap])

• Example:

<?php
echo "The output of date() function”;
echo date("d");
echo date("D");
echo date("j");
?>

date() function formats
Required. Specifies how to return the result:
d - The day of the month (from 01 to 31)
D - A textual representation of a day (three letters)
j - The day of the month without leading zeros (1 to 31)
l (lowercase 'L') - A full textual representation of a day
N - The ISO-8601 numeric representation of a day (1 for
Monday through 7 for Sunday)
S - The English ordinal suffix for the day of the month (2
characters st, nd, rd or th. Works well with j)
w - A numeric representation of the day (0 for Sunday
through 6 for Saturday)
z - The day of the year (from 0 through 365)
W - The ISO-8601 week number of year (weeks starting
on Monday)

F - A full textual representation of a month (January through
December)
m - A numeric representation of a month (from 01 to 12)
M - A short textual representation of a month (three letters)
n - A numeric representation of a month, without leading
zeros (1 to 12)
t - The number of days in the given month
L - Whether it's a leap year (1 if it is a leap year, 0 otherwise)
o - The ISO-8601 year number
Y - A four digit representation of a year
y - A two digit representation of a year


a - Lowercase am or pm
A - Uppercase AM or PM
B - Swatch Internet time (000 to 999)
g - 12-hour format of an hour (1 to 12)
G - 24-hour format of an hour (0 to 23)
h - 12-hour format of an hour (01 to 12)
H - 24-hour format of an hour (00 to 23)
i - Minutes with leading zeros (00 to 59)
s - Seconds, with leading zeros (00 to 59)
e - The timezone identifier (Examples: UTC, Atlantic/Azores)
I (capital i) - Whether the date is in daylights savings time (1 if
Daylight Savings Time, 0 otherwise)
O - Difference to Greenwich time (GMT) in hours (Example:
+0100) Developed By: Amit Lakhani, TFGP Adipur

T - Timezone setting of the PHP machine (Examples: EST,
MDT)
Z - Timezone offset in seconds. The offset west of UTC is
negative, and the offset east of UTC is positive (-43200
to 43200)
c - The ISO-8601 date (e.g. 2004-02-12T15:19:21+00:00)
r - The RFC 2822 formatted date (e.g. Thu, 21 Dec 2000
16:01:07 +0200)
U - The seconds since the Unix Epoch (January 1 1970
00:00:00 GMT)


getdate() function
• returns an array containing the date information of the
timestap.

• Syntax: array getdate([int $timestap])

• Example:
<?php
echo "The output of getdate() function<br>";
print_r(getdate());
?>


setdate() function
• Resets the current date of the datetime object to a
different date.
• Syntax: DateTime::setDate(int $y, int $m, int $y)

• Example:

<?php
echo "The output of setdate() function<br>";
$d=new DateTime();
$d->setDate(2011,4,2);
echo $d->format('d-m-y');
?>

checkdate() function
• Checks the validity of the date formed by the argument

• Syntax: bool checkdate(int $m, int $d, int $y)

• Returns TRUE if the given date is valid

• Example:

<?php
echo "The output of checkdate() function<br>";
print_r(checkdate(11,30,2000));
?>

time() function
• Returns the current UNIX timestamp

• Syntax: int time (void)

• Returns the current time measured in number of
seconds ( Jan 1 1970 00:00:00 GMT)

• Example:

<?php
echo "The output of time() function<br>";
echo time();
?>

mktime() function
• Returns the UNIX timestamp corresponding to the
arguments given.

• Syntax: int mktime($hrs, $mins, $sec, $mnt, $day, $yr)

•Example:

<?php
echo "The output of mktime() function<br>";
echo mktime();
echo(date("M-d-Y",mktime(0,0,0,12,36,2001)));
echo(date("M-d-Y",mktime(0,0,0,14,1,2001)));

3.5
Array functions


Array functions
count() -Counts all elements in an array, or properties in
an object

array_count_values()-Returns an array of values from input
as keys and their count as value.

list() -Assigns variables to values

In_array()-checks if a value exists in an array

current() -Return the current element in an array

next()-Advance the internal array pointer of an array

Array functions conti..
prev()-Rewind the internal pointer of an array

end()-Set the internal pointer of an array to its last element

each()-Returns the current key and value pair from an array
and advances the array cursor
sort()-Sorts an array

Array_merge()-Merges the elements of one or more array
together so that the values of one or more are appended to
the end of the previous array.


Array functions conti..
Array_reverse()-Returns the array with the order of the
elements reversed.

Array_sum()- Returns the sum of values in an array


count() function
• Counts all elements in an array, or properties in an object

• Syntax: count($var)

• Example:

<?php
echo "The number of elements in first
array=".count($varArray);
?>
Output:


Array_count_values() function
• Returns an array of values from input as keys and their
count as value.

• Syntax: array array_count_values($var)

• Example:
<?php
echo "The output of array_count_values() function<br>";
$arr=array(1,2,3,4,5);
print_r(array_count_values($arr));
?>
Output:


list() function
• Assigns variables to values

• Syntax: list($var1, $var2,…..)

Example:

<?php
echo "The output of list() function<br>";
$arr=array(1,2,3);
list($a,$b,$c)=$arr;
echo “The list of values are:<br> $a <br> $b <br> $c ";
?>

In_array() function
• checks if a value exists in an array

• Syntax: in_array($key, $array)

• Example:
<?php
$varArray=array(1,2,3);
if(in_array(1,$varArray))
{
}
?>


current() function
• Return the current element in an array

• Syntax: mixed current($array)

• Example:
<?php
$arr=array(1,2,3);
echo "The current element is ". current($arr);
?>
Output:


next() function
• Advance the internal array pointer of an array

• Syntax: mixed next($array)

• Example:
<?php
$arr=array(1,2,3);
echo "<br>The next element is ". next($arr);
?>
Output:


prev() function
• Rewind the internal pointer of an array

• Syntax: mixed prev($array)

• Example:
<?php
$arr=array(1,2,3);
echo "<br>The next element is ". next($arr);
echo "<br>The next element is ". prev($arr);
?> Output:


end() function
• Set the internal pointer of an array to its last element

• Syntax: mixed end($array)

• Example:

<?php
$arr=array(1,2,3);
echo "The last element is ". end($arr);
?>
Output:


each() function
• Returns the current key and value pair from an array
and advances the array cursor

• Syntax: array each($array)

• Example:
<?php
$arr=array(1,2,3);
$ele=each($arr);
echo "The element is ";
print_r($ele);
?>


sort() function
• Sorts an array

• Syntax: bool sort($array)

• Example:

<?php
$arr=array(1,2,3);
sort($arr);
print_r($arr);
?>
Output:


Array_merge() function
• Merges the elements of one or more array together so
so that the values of one or more are appended to the
end of the previous array.

• Syntax: array array_merge($array1, $array2, …..)

• Example:
<?php
$arr=array(1,2,3);
$arr_1=array(4,5,6);
$arr_2=array_merge($arr, $arr_1);
print_r($arr_2);
?>

Array_reverse() function
• Returns the array with the order of the elements
reversed.

• Syntax: array array_reverse($array)

• Example:
<?php
$arr=array(1,2,3);
$arr_2=array_reverse($arr);
print_r($arr_2);
?>
Output:


Array_sum() function
• Returns the sum of values in an array

• Syntax: number array_sum($array)

• Example:

<?php
$arr=array(1,2,3);
$arr_2=array_sum($arr);
print_r($arr_2);
?>
Output:


3.6
File functions


File functions
fopen()- opens a file or URL

fread()- it reads from an open file

fwrite()- Writes the contents of string to the file stream

fclose()- closes an open file


fopen() function
• Opens a file

• Syntax: fopen(filename, mode)

• Example: File name File mode

<?php
$file = fopen("test.txt","w");
echo fwrite($file,"computer department");
fclose($file);
?>


fopen() file modes
‘r’ Open for reading only. Start at beginning of
file.
‘r+’ Open for reading and writing. Start at
beginning of file.
‘w’ Open for writing only. Remove all previous
content, if file doesn’t exist, create it.
‘w+’ Open for reading and writing. If file doesn’t
exist, attempt to create it.
‘a’ Open writing, but start at END of current
content.


fopen() file modes

‘a+’ Open for reading and writing, start at END
and create file if necessary.
‘x’ Create and open for writing only.

‘x+’ Create and open for reading and writing .


fread() function
• Reads from an open file

• Syntax: fread(file,length)

• Example:
<?php
$file = fopen("test.txt","r");
echo fread($file,5);
fclose($file);
?>


fwrite() function
• Writes the contents of the string

• Syntax: fwrite(filename, mode)

• Example:

<?php
fclose($file);
?>


fclose() function
• Closes an open file.

• Syntax: fclose($filename)

• Example:

<?php
fclose($file);
?>


Summary
PHP offers several built in functions for day to day
uses in coding

• Variable functions • Date functions

• String functions • Array functions

• Math functions • File functions


Chapter - 4

Working with Data

Working with Data
• This unit covers….
4.1 FORM element, INPUT element

4.2 Processing the form

4.3 User Input

4.4 Adding Items

4.5 Validating the user input

4.6 Passing variables between pages

4.1
FORM element,
INPUT element


Concept of Form element
• If you want to design a page , which accepts
Information from users through various fields such
as textbox, textarea, checkbox, radio buttons, drop
down list etc at that time you have to use the form
control.

• Form can be defined using <form> tag.

• Forms are used to pass data to a server.

• The syntax to put form control is:
<form> </form>

Form element example
<html>
<form> Form element
First Name:
<input type= "text" name="txtfname">
<br>
Last Name:
<input type= "text" name="txtlname" >
<br>
<input type= "submit" name="btnsubmit"
value = "Send">
</form> Form element
</html>

Form element output


Form attributes
The form attributes are as follows:
Action: - It is the URL program that is going to accept the
data from the form, process it, and send a
response back to the browser.
Method:- GET(default) or POST specifies which HTTP
method will be used to form’s content to the
web server.
Enctype:- This determines the mechanism used to
encode the form content.
Name:- This is form name.
Target:- This is the target frame where the response page
will show up.

Form elements
The form elements are:

• Textboxes
• Password boxes
• Check boxes
• Option buttons
• Submit
• Reset
• File
• Hidden
• Image


Input elements
The input elements are used to get input from the user
In various format:

• Type:- type of input entry field
• Name:- variable name passed to application
• Value:- the data associated with the variable name to
be passed to the application
• Checked :- Button/ box checked by default
• Size:- number of character in text field
• Maxlength :- maximum number of characters
accepted


Input elements conti…..
Following are the list of commonly used input fields:
• Hidden:- used to send data that you don’t want the
web surfer to see.
• Textbox:- used to provide input fields for text, phone
numbers, dates etc.
• Password:- used to allow entry of password.
• Text area:- allows free form text entry.
• Checkbox:- allows the user to select more than one
option
• Radio button:- allow users to select only one option.
• Select:- used to select one or more option from given
list


• Option:- The list items are added to the <SELECT>
element by inserting <OPTION> element.
• Dropdown list:- it is used to select one option from
list.
• List :- it is used to select one option from list.
• Push Button :- would cause an action to take place.
• Submit:- it causes the browser to send the names and
values of the other elements to the
application specified by the ACTION attribute
of the FORM element



• Image submit button:- allows to substitute an image
for the standard submit button.
• Reset:- It allows the user to clear all the input in the
form.


Hidden Input
It is used to send data to the application that you don’t
Want the user to see or have to enter but is necessary
for the application to process the form correctly.

<INPUT TYPE= “HIDDEN”>
Attributes:
•Type:- hidden
• Name:- variable name to be sent to the application
• Value:- usually set to the value expected by the
applicaton


Textbox Input
It is used to provide input fields for text, phone numbers,
dates etc.
<INPUT TYPE= “TEXT”>
Attributes:
• Type:- text
• Size:- determine the size of textbox in characters
(default=20)
• Maxsize :- determine the maximum number of
characters that the field will accept
• Value:- will display its contents as the default value


Example of Textbox input
<html>
<form>
<font size=50> Textbox element
First Name:
<input type= "text" name="txtfname“>
Last Name:
<input type= "submit" name="btnsubmit" value =
"Send">
</form>
</html>


Output of Textbox example

Textbox


Password Input
It is used to allow entry of password

<INPUT TYPE= “PASSWORD”>
Attributes:
• Type:- password
• Size:- determine the size of textbox in characters
• Maxsize :- determine the maximum size of password
in characters.
• Value:- usually blank


Example of Password input
<html>
<form>
<font size=50>
Username:
<input type= "text" name="txtuname“>
Password:
<input type= “password" name="txtpwd”>
<input type= "submit" name="btnsubmit" value =
"Send">
</form>
</html> password


Output of Password example

password


Text area Input
It allows the user to type address, comments etc.
having multiple lines.
<TEXTAREA> </TEXTAREA>
Attributes:
• Rows:- number of rows to the textbox
• Cols:- number of columns to the textbox
• Wrap:- default OFF. It is set so that the text wraps in
the browser


Example of textarea input
<html>
<form>
Text area input
<font size=20>
Name:
Address:
<textarea name="txtadd" rows=5 ></textarea>
<input type= "submit" name="btnsubmit" value = "Send" >
</form>
</html>


Output of textarea example

Text area


Checkbox Input
It allows the user to select more than one option.

<INPUT TYPE= “CHECKBOX”>
Attributes:
• Type:- checkbox
• Checked:- blank or CHECKED as the initial status
• Value:- usually set to a value


Example of Checkbox input
<html>
Checkbox element
<form>
Select Your Department:<br>
<input type= "checkbox" name="chkdept"
value="dept">Computer<br>
value="dept">Information Technology<br>
value="dept">Mechanical<br>
value="dept">Electrical
</form>
</html> Developed By: Amit Lakhani, TFGP Adipur

Output of checkbox example

checkbox


Radio button Input
It allows the user to select only one option.

<INPUT TYPE= “RADIO”>
Attributes:
• Type:- radio
• Checked:- blank or CHECKED as the initial status. Only
one radio button can be checked
• Value:- usually set to a value


Example of Radio button input

<html>
<form>
Radio button element
<font size=5>
Select Your Gender:
<input type= "radio" name="rdgender"
value="male">Male<br>
<input type= "radio" name="rdgender"
value="female">Female<br></form>
</html>


Output of Radio button example

Radio buttons


Select Input
It is used to select one or more option from given
list of choice
<SELECT> </SELECT>
There are two types of select input:
• Dropdown list- it is like combobox control.
• List box- it is like list control.

Attributes:
•Name:- variable name to be sent to the application.
• Size:- sets the number of visible choices.
• Multiple:- presense of this attribute allow the user to
make multiple selection

Option Input
List items are added to the <OPTION> </OPTION>
Element.
<OPTION> </OPTION>
Attributes:
• Selected:- When this attribute presents, the option is
selected when the document is initially
loaded.
• Value:- Specifies the value the variable named in the
select element.


Example of select input with dropdown menu

<html>
<form>
Select Your Gender:<br>
<select name="lang">
<option > English</option>
<option selected> Hindi</option>
<option> Gujarati</option>
</select>
</html>
Select with option element

Output of select example with dropdown menu

Select input with dropdown box

Selected value


Example of select input with list box

<html>
<form>
Select Your Language:<br>
<select name="lang" size=3 multiple="true">
<option > English</option>
<option selected > Hindi</option>
<option> Gujarati</option>
</select>
</html>
Select with option element

Output of select example with list box

Select input with list box

Multiple Selected value


Push Button
This element would be used to cause an action to take
place
<INPUT TYPE=“BUTTON”>
Attributes:
• Type:- Button
• Name:- Specifies the name to be used in scripting.
• Value:- determine the text label on the button.


Example of push button

<html>
<form>
First Name:
Last Name:
<input type= “button" name="btnsubmit" value =
"Send">
</form>
</html> Push button input


Output of push button

button


Submit button
This element causes the browser to send the names of
And values of the other elements to the application
Specified by the ACTION attribut of the FORM element
<INPUT TYPE=“SUBMIT”>
Attributes:
• Type:- submit


Example of submit button

<html>
<form>
First Name:
Last Name:
<input type= “submit" name="btnsubmit" value =
"Send">
</form>
</html> submit button input


Output of submit button

Submit button


Image Submit button
Allows user to substitute an image for the standard
Submit button.
<INPUT TYPE=“IMAGE” SRC= …URL>
Attributes:

• Type:- image
• SRC:- URL of the image file.


Example of image submit button

<html>
<form>
First Name:
Last Name:
<input type= “image“ src=”…” name="btnsubmit"
value = "Send">
</form>
</html> submit button input


Output of image submit button

image button


Reset button
Allows user to clear all the input in the form.

<INPUT TYPE=“RESET”>
Attributes:

• Type:- reset


Example of reset button

<html>
<form>
First Name:
Last Name:
<input type= "submit">
<input type= "reset">
</form>
</html> reset button input


Output of reset button

reset button


4.2
Processing the form


Concept of Processing the form
• We can use any of the form elements to send or retrieve
the data to or from PHP pages. You can store values
Retrieved from form into variables in order to use these
values.

• When you create a form you have two choices for the
METHOD attribute. You can use one of the following two
methods to pass information between pages.
• GET method
• POST method

• They both pass the data entered into the form along with
the form field name to the web server.

Processing the form
• GET method
When GET method is used in the METHOD attribute
of FORM element, the value entered in the input
elements are displayed in URL.


Processing the form
• POST method
When POST method is used in the METHOD
attribute of FORM element, the value entered in the
input elements are not passed in the URL.

Output of post method


Example of form processing using GET method
Form_get.php
<html><body>
<form action="get.php" method="get">
Name: <input type="text" name="fname" />
Age:<input type="text" name=“surname" />
<input type="submit" value=“Send”/>
</form></body></html>
get.php
<?php
echo "Name:".$_GET['fname'];
echo "<br>";
echo "Surname:".$_GET['surname'];

Output of form
Output of form_get.php

When “Send”
button is clicked,
value in the text
box is sent to the
get.php and are
displayed in
browser
Output of get.php


Example of form processing using POST method
Form_post.php
<html><body>
<form action=“post.php" method=“post">
Age:<input type="text" name=“surname" />
<input type="submit" value=“Send”/>
post.php
<?php
echo "Name:".$_POST['fname'];
echo "<br>";
echo "Surname:".$_POST['surname'];

Output of form
Output of form_post.php

When “Send”
button is
clicked, value in
the text box is
sent to the
post.php and are
displayed in
Output of post.php browser


4.3
User input


4.3 User input

4.3.1 INPUT checkbox type
4.3.2 One form multiple processing
4.3.3 Radio INPUT element
4.3.4 Multiple submit buttons
4.3.5 Basic input testing
4.3.6 Dynamic page title
4.3.7 Manipulating string as an array


4.3.1
INPUT checkbox type


4.3.2
One form
multiple processing


Concept of One form, multiple processing

• You can create a single form having many submit
button for a variety of actions to be performed.

• For, example, you can have a database application in
which a form may contain more than one buttons for
insertion, deletion, searching etc. The page which
receives the form data will then process the operations
accordingly.


4.3.3
Radio INPUT element


4.3.4
Multiple submit button


Concept of multiple submit button

• You can create a single form having many submit
button for a variety of actions to be performed.

• The submit button can share the same name but supply
different values.

• Clicking one of these buttons will cause the browser to
submit the form accordingly


Example of form with multiple submit
<html><body>
<form action="multiple_submit_post.php"
method="post" >
Name:<input type="text" name="fname" />
Address: <textarea name="address"> </textarea>
<input type="submit" name="display" value="Show
Name" />
<input type="submit" name="display" value="Show
Address" />
</form> Multiple submit in a form, each
</body> button must have same name
</html>

Example of form with multiple submit
Multiple_submit_post.php

<?php
if ($_POST['display']=="Show Name")
{
echo "Your name is:" .$_POST['fname'];
}
Here, we just check for the value submitted for the
else Submit button
{
echo " Your Address is:" .$_POST['address'];
}
?>

Output of form with multiple submit
Output of form_multiple_submit.php

Depending on
the button you
click and the data
you choose
To enter , this
code outputs
different
Output of multiple_submit_post.php information.


4.3.5
Basic Input testing


Concept of input testing
• Input testing involves verification that the data you
receive from a client is in fact in the form you planned
on receiving.

• Invalid data cause two major problems in code
• Trash data- that does not match the specification
• Altered data- intentionally obscured

• A common tactic is used to address this is to use drop
down boxes to provide users a choice of state.


• In PHP script input testing is done using the same way
as JavaScript validation.

• Before using user input for processing we need to check
the following information:
• Does the user supply all mandatory information?
• Is the information provided contains valid and
meaningful data?
• Is the submitted information conforming to the
standard? (dd/mm/yyyy)


Basic input test are:

• Check whether a variable is a number or numeric string:
$result = is_numeric($string);

• Check whether a string contains only alphanumeric
characters(alphabetic/numeric):
$result = ctype_alnum($ string);

• Check whether a string contains simply alphabetic
characters(letters a to z):
$result = ctype_alpha($ string);



• Check whether a string contains only digits:
$result = ctype_digit($ string);

• Check whether a string contains only hexadecimal digits:
$result = ctype_xdigit($ string);

• Check whether a string is completely upper/lower case:
characters(letters a to z):
$result = ctype_upper($ string);
$result = ctype_lower($ string);



• Forces a variable to be a specific type:
$result = settype($variable, $type);

• Interpret a variable as a certain type using type-casting:
$result = (datatype) $variable;


Example of input testing
Form_validation.php
<html><body>
<form action="validation_post.php" method="post" >
Name:<input type="text“ name="fname" />
Surname: <input type="text" name="surname" />
<input type="submit" value="Send" />
Validation_post.php
<?php
$result=$_POST['fname'];
if (ctype_digit($result)=="TRUE")
echo "Please enter alphabets only in Name";
else
echo "You have entered correct informaion";
?>
Check whether a string contains only digits

Example of Input testing
Output of form_validation.php

Check whether a
string contains
only digits, if the
digits are entered
in name, it warns
user to enter only
alphabet in name
Output of validation_post.php


4.3.6
Dynamic Page Title


Concept of dynamic page title

• When displaying the web page to the user we can
change the title of the page dynamically using <title> tag
with a little bit effort of PHP code within <title></title> .

• There are two ways to display title of the page
dynamically:

• When title of the page is set
• When title of the page is not set


Example of dynamic title when title is set
Dynamic_title.php
<html><head>
<?php isset($title) ? $title : "Default title";?>
</head>
<body> Dynamic title is set
<?php
$title="Example of dynamic title";
require_once("dynamic_title_header.php"); output
?></body></html>
Dynamic_title_header.php
<title>
<?php
if (isset($title))
print $title;
Else
print "default title";
?></title> Developed By: Amit Lakhani, TFGP Adipur

Example of dynamic title when title is not set
Dynamic_title.php
<html><head>
<?php isset($title) ? $title : "Default title";?>
</head>
<body> default title is set
<?php
require_once("dynamic_title_header.php");
?></body></html> output

Dynamic_title_header.php
<title>
<?php
if (isset($title))
print $title;
Else
print "default title";
?></title> Developed By: Amit Lakhani, TFGP Adipur

4.3.7
Manipulating the string
as an array


Concept of string as an array

• In PHP, two types of data need special attention and a
more complete explanation i.e. array and string

• Actually strings are array of characters i.e. group of
• characters, it means following two statements are same:

$string=“computer”;
$string=array(‘c’,’o’,’m’,’p’,’u’,’t’,’e’,’r’);
• This states that we can use string as an array and we can
manipulate string as an array using functions.


Functions that is used to convert string as array

• str_split() :- it splits string into an array.

• explode():- it breaks a string into an array.

• implode() :- returns a string from the element of an array.


Str_split() function
• splits a string into an array.

• Syntax: str_split(string, length)

• Example:
<?php
Print_r(str_split(“computer”));
?>
Splits the string
Output:


explode() function
• breaks a string into an array.

• Syntax: explode(separator, string, limit)

• Example:
<?php
$str="Hi, This is computer department";
print_r(explode(",",$str));
print_r(explode(" ",$str)); breaks the string
print_r(explode(" ",$str,3));
?>

Output of explode() function
breaks the string with seperator “,”

breaks the string with seperator “ ”

breaks the string with seperator “ ”


implode() function
• returns a string from the element of an array

• Syntax: implode(separator, array)

• Example:
<?php
$arr=array('computer', 'department');
echo implode(" ",$arr);
?> return string with space
Output:


4.4
Adding Items


Adding items to an array and copy whole array
• to add an item to an array use [ ] operator

• to copy a whole array

• Example:
<?php
$dept[0]="IT";
$dept[1]="Computer";
$dept[2]="Mech"; Copy whole array
$department=$dept;
echo $department[1];

4.5
Validating user input


Client side validation
•You can write scripting code that will verify form
fields contain good data before being submitted
to the server.
• Most client side validation is completed using the
special “onSubmit” event of a form, which allows
you to run Java script code to handle form
validation when your visitor attempts to submit
the form.
• If you return false from your code in “onSubmit”,
web browser will not proceed with submitting the
form, which allows you to prompt visitors to
correct any error before submission.

Server side validation

• It means using PHP to verify that good values
have been sent to the script.
• It is more secure and works seamlessly with all
browser, but it does so at the cost of higher server
load and slower feedback for users.
• Any sensible site should include server side
validation of variables, because they are harder
to hack and they will work no matter what browser
your visitors are using.


4.6
Passing variables
Between pages


4.6 Passing variables between pages

4.6.1 Passing variable through URL
4.6.2 Passing variable through sessions
4.6.3 Passing variable through cookie
4.6.4 Passing variable through forms


4.6.1
Passing variables
with URL


Passing variables through URL
•There are various ways to pass data between
pages, one of the way is to use the URL to pass the
values through GET method.

• The advantage is we can pass data to a different
sites running at different server.

• Main concern is the data gets exposed in address
bar of the browser and can be easily accessed by
using browser history.


4.6.2
Passing variables
with session


Passing variables with session

• HTTP is stateless protocol which means that each
server request knows nothing about the others.

• A PHP session variable is used to store information
about, or change settings for a user session.

• Session variables hold information about one
single user, and are available to all pages in one
application.


Passing variables with session conti..
• When you are working with an application, you open
it, do some changes and then you close it. This is
much like a Session. The computer knows who you
are.

• It knows when you start the application and when
you end. But on the internet there is one problem:
the web server does not know who you are and
what you do because the HTTP address doesn't
maintain state.


Passing variables with session conti..
• A PHP session solves this problem by allowing
you to store user information on the server for
later use (i.e. username, shopping items, etc).

• However, session information is temporary and will
be deleted after the user has left the website. If you
need a permanent storage you may want to store
the data in a database.

• Sessions work by creating a unique id (UID) for
each visitor and store variables based on this UID.
the UID is either stored in a cookie or is propagated
in the URL.

Starting a session
• Before you can store user information in your
PHP session, you must first start up the
session.

• The session_start() function must appear
BEFORE the <html> tag:
Start the session using
Example function

<?php session_start(); ?>
<html><body>
</body></html>


Storing a session variable
• The correct way to store and retrieve session
variables is to use the PHP $_SESSION
variable:
Example Store session variable using
$_SESSION[] superglobal
<?php
session_start();
// store session data
$_SESSION['views']=1;
?>


Destroy a session variable
• If you wish to delete some session data, you
can use the unset() or the session_destroy()
function.
•You can completely destroy the session by
calling the session_destroy() function:
<?php
session_destroy();
?>
•The unset() function is used to free the
specified session variable:
<?php
unset($_SESSION['views']);

Session example
Session_form.php
When submit is clicked
session_post.php is called
<html>
<body>
<form action="session_post.php" method="post">
<input type="submit" name="btnsub"/>
</form>
</body>
</html>


Session example User input is fetched in
Session_post.php session variable
<?php
session_start();
$_SESSION['name']=$_POST['fname'];
$myname=$_SESSION['name'];
echo "Wel come:<b>" .$myname."<b><br>";
if(isset($_SESSION['views']))
$_SESSION['views']=$_SESSION['views']+1;
else
$_SESSION['views']=1;
echo "You visited this page=". $_SESSION['views'];
echo " times.";
?>

Session example output
Session_form.php

session_post.php is called
and session variable is
called
Session_post.php


4.6.3
Passing variables
with cookies


Passing variables with cookies

• A cookie is often used to identify a user.

• A cookie is a small file that the server embeds on
the user's computer. Each time the same
computer requests a page with a browser, it will
send the cookie too.

• With PHP, you can both create and retrieve
cookie values.


Setting cookies
• The setcookie() function is used to set a cookie.

• The setcookie() function must appear BEFORE
the <html> tag.

Syntax
setcookie(name, value, expire, path, domain);

•Once the cookies have been set, they can be
accessed on the next page load with the
$_COOKIE or $HTTP_COOKIE_VARS arrays.


Setting cookies conti..
• cookie parameters:
Parameters Meaning
name The name of the cookie.
value The value of the cookie.
This value is stored on the
clients computer; do not
store sensitive information.
Assuming the name is
'cookiename', this value is
retrieved through
$_COOKIE['cookiename']



Parameters Meaning
expire The time the cookie
expires. This is a Unix
timestamp so is in number
of seconds since the epoch.
If set to 0, or omitted, the
cookie will expire at the
end of the session (when
the browser closes).



Parameters Meaning
path The path on the server in
which the cookie will be
available on. The default
value is the current
directory that the cookie is
being set in.


Setting cookies
Parameters Meaning
domain The domain that the cookie
is available to. Setting the
domain to www will make
the cookie only available in
the www subdomain.
secure Indicates that the cookie
should only be transmitted
over a secure HTTPS
connection from the client.


Creating Cookie
cookie.php
Cookie value
Cookie name
<?php
setcookie("user", "Amit Lakhani", time()+3600);
?>
<html> Cookie expiry
<form action="wc1.php" method="post">
<input type="submit">
</form
</html>
wc1.php is called


Accessing Cookie using $_COOKIE
wc1.php
Accessing
<html> Cookie value
<body>
<?php
if (isset($_COOKIE["user"]))
echo "Welcome " . $_COOKIE["user"] . "!<br />";
else
echo "Welcome guest!<br />";
?>
</body>
</html>


Destroying Cookie
When deleting a cookie you should assure that
the expiration date is in the past.

Example:
<?php
// set the expiration date to one hour ago
setcookie("user", “Amit Lakhani", time()-3600);
?>

expiration date to one
hour ago


4.6.4
Passing variables
with forms


Concept of $_REQUEST variable
•The PHP built-in $_REQUEST function contains
the contents of both $_GET, $_POST, and
$_COOKIE.

•The $_REQUEST function can be used to collect
form data sent with both the GET and POST
methods.

Example
<?php
echo $_REQUEST["fname"]; ?>!<br />
?>

$_REQUEST example
Form_request.php
<html><body>
<form action="request.php" method="post" >
request.php Get the value of input
<?php
echo “Name:”$_REQUEST*'fname'];
echo "Surname:”$_REQUEST*'surname'+;
?>

Output of $_REQUEST example
Form_request.php

request.php Get the value of input
using $_REQUEST


Self processing
HTML Forms


Concept of $_PHP_SELF superglobal
• The PHP default variable $_PHP_SELF is used
for the PHP script name and when you click
“submit” button then the same PHP script will be
called and will produce the result.
Value of action property is
• Example: set to $_PHP_SELF

<html><body>
<form action="<?php $_PHP_SELF ?>" method="post">


Example of $_PHP_SELF superglobal
<?php
if (isset($_POST['fname']))
{
When
echo "welcome:".$_POST['fname']; submit is
exit(); clicked it
executes
} the
?> above
script
<html><body>
<form action="<?php $_PHP_SELF ?>" method="post">

Browser
Redirection


Concept of browser redirection

• The header() function sends a raw HTTP header
to a client.

• It is important to notice that header() must be
called before any actual output is sent

• Syntax
header(string,replace,http_response_code)


Concept of browser redirection
header parameters:

Parameter Description
string Required. Specifies the header string
to send
replace Optional. Indicates whether the
header should replace previous or
add a second header. Default is TRUE
(will replace). FALSE (allows multiple
headers of the same type)
http_response_code Optional. Forces the HTTP response
code to the specified value (available
in PHP 4.3 and higher)

Example of header() function
<?php
header("Content-Type: image/jpeg");
header("Content-Disposition: attachment;
filename=file.jpg");
?>


Example of header() function
<?php
header("Location:http://www.google.com");
?>


Summary
• FORM element, INPUT element

• Processing the form

• User Input

• Adding Items

• Validating the user input

• Passing variables between pages


Chapter - 5

Error Handling

Error handling

5.1 Error types in PHP

5.2 Generating PHP errors

5.3 Exceptions

5.4 Not meeting conditions

5.5 Parse errors


Error
Handling


Concept of error
• Error handling is the process of catching errors
raised by your program and then taking appropriate
action.

• When creating scripts and web applications,
error handling is an important part.
If your code lacks error checking code, your
program may look very unprofessional and you
may be open to security risks.

• The default error handling in PHP is very simple.
An error message with filename, line number and
a message describing the error is sent to the
browser. Developed By: Amit Lakhani, TFGP Adipur

5.1
Error Types in PHP


Types of error
• There are main four categories of errors in PHP
• Fatal error – critical errors ( instantiating an
object of a non existence class or calling a
non existence function). It cause the immediate
termination of the script and PHP’s default
behavior is to display them to the user when
they take place.

• Notice – trivial or non critical errors that PHP
encounters when executing a script. E.g
accessing a variable that has not yet been
defined. Such errors are not displayed to users.

Types of error
• There are main four categories of errors in PHP

• Warning – serious errors, e.g attempt to
include a file which does not exists. This errors
are displayed to users but they don’t result in
script termination.

• Parse– compile time errors. When we make
mistake in code e.g missing a semicolon or any
unexpected symbol then paneraterse errors are
generated.


Error predefined constants
E_NOTICE Detection of a situation that could indicate a
problem, but might be normal.
E_USER_NOTICE User triggered notice.
E_WARNING Actionable error occurred during execution.
E_USER_WARNING User triggered warning.
E_COMPILE_WARNIN Error occurred during script compilation
G (unusual)
E_CORE_WARNING Error during initialization of the PHP engine.
E_ERROR Fatal run-time error
E_USER_ERROR User triggered fatal error.
E_COMPILE_ERROR Critical error occurred while trying to read
script.
E_CORE_ERROR Occurs if PHP engine cannot startup/etc.
E_PARSE Raised during compilation in response to
syntax error

5.2
Generating PHP
errors


Generating error
<?php
$str="This is error example";
$string=strtoupper(); Error warning
?>


Error handling using die() function
The first example shows a simple script that opens a
text file:

<?php
$file=fopen("welcome.txt","r");
?>

If the file does not exist you might get an error like this:
Warning: fopen(welcome.txt) [function.fopen]: failed to
open stream:No such file or directory in
C:webfoldertest.php on line 2


Error handling using die() function conti..
To avoid that the user gets an error message like the
one above, we test if the file exist before we try to
access it:

<?php
if(!file_exists("welcome.txt")) handle error using die()
{
die("File not found");
}
else
{
$file=fopen("welcome.txt","r");
}

5.3
Exception Handling


Concept of exception
• Exception handling is used to change the normal
flow of the code execution if a specified error
(exceptional) condition occurs. This condition is
called an exception.
• This is what normally happens when an exception
is triggered:
• The current code state is saved
• The code execution will switch to a predefined
(custom) exception handler function
• Depending on the situation, the handler may
then resume the execution from the saved code
state, terminate the script execution or continue
the script from a different location in the code.

Concept of exception conti..
• Exceptions should only be used with error
conditions, and should not be used to jump to
another place in the code at a specified point.

• The different error handling methods:

• Basic use of Exceptions
• Creating a custom exception handler
• Multiple exceptions
• Re-throwing an exception
• Setting a top level exception handler


Basic Use of Exceptions

• PHP uses try/catch method to handle exception.

• When an exception is thrown, the code following it
will not be executed, and PHP will try to find the
matching "catch" block.

• If an exception is not caught, a fatal error will be
issued with an "Uncaught Exception" message.


Exception example
<?php
//create function with an exception
function checkNum($number)
{ throw an uncaught exception
if($number>1)
{
throw new Exception("Value must be 1 or below");
}
return true;
}
checkNum(2);
?>

Exception example output

throw an uncaught exception


Use try, throw,
catch


Using try, throw and catch
• To avoid the error to be handled by the PHP engine,
we need to create the proper code to handle an
exception.
• Proper exception code should include:
•Try - A function using an exception should be in a
"try" block. If the exception does not trigger, the
code will continue as normal. However if the
exception triggers, an exception is "thrown"
• Throw - This is how you trigger an exception.
Each "throw" must have at least one
"catch"
• Catch - A "catch" block retrieves an exception and
creates an object containing the exception
information

Exception example
<?php
function checkNum($number) throw an exception
{
if($number>1) 2
{
throw new Exception("Value must be 1 or below");
}
return true; 1
} caught
try exception
{
checkNum(2);
echo 'If you see this, the number is 1 or below'; 3
}
catch(Exception $e)
{
echo 'Message: ' .$e->getMessage();
}
?>

Exception example explaind
The code above throws an exception and catches it:
1. The checkNum() function is created. It checks if a
number is greater than 1. If it is, an exception is
thrown.
2. The checkNum() function is called in a "try" block
3. The exception within the checkNum() function is
thrown
4. The "catch" block retrives the exception and
creates an object ($e) containing the exception
information
5. The error message from the exception is echoed
by calling $e->getMessage() from the exception
object

Creating custom
exception class


Creating custom exception class
• It is simple to create a special class with functions
that can be called when an exception occurs in
PHP.
• The class must be an extension of the exception
class.
• The custom exception class inherits the properties
from PHP's exception class and you can add
custom functions to it.

class customException extends Exception
{
public function errorMessage()


Custom exception class example
<?php try
class customException extends {
Exception $a=25;
{ $b=0
public function errorMessage() if($b==0)
{ {
$errorMsg = 'Error on line '.$this- //throw exception if email is not valid
>getLine().' in '.$this->getFile() throw new customException($b);
.': <b>'.$this->getMessage().'</b> }
is not a valid denominator; }
return $errorMsg; catch (customException $e)
} {
} //display custom message
echo $e->errorMessage();
}
?>


Nesting
Exception


Concept of nesting exception
• We can also put one try block inside another try
block, this is called nesting of exceptions.

• In nested exception when the inner try block will be
executed and exception is thrown then the
matching inner catch block will be executed.

• If no inner catch block can handle the generated
exception than the outer catch block will handle the
exception.


Concept of nesting exception conti..
Class sample
{
Public function testing()
{
try
{
try {
};
catch {
}; outer block
}
catch()
{ inner block
}
}
} Developed By: Amit Lakhani, TFGP Adipur

Multiple
Exception


Concept of multiple exception

• It is possible for a script to use multiple exceptions
to check for multiple conditions.

• It is possible to use several if..else blocks, a
switch, or nest multiple exceptions. These
exceptions can use different exception classes and
return different error messages.


Example of multiple exception
<?php catch (Exception1 $e)
class Exception1 extends Exception {
{} echo $e->getMessage();
class Exception2 extends } multiple
Exception1 {} catch block
class test catch(Exception2 $e)
{
{
echo $e->getMessage();
public function testing() }
{ catch (Exception $e)
try {
{ echo $e->getMessage();
throw new Exception1("PHP }
exception handling"); }
} };
$ob= new test;
$ob->testing();
?>


Rethrowing
Exception


Concept of rethrowing exception
• Sometimes, when an exception is thrown, you may
wish to handle it differently than the standard way.

• It is possible to throw an exception a second time
within a "catch" block.

• A script should hide system errors from users.

• System errors may be important for the coder, but
is of no interest to the user. To make things easier
for the user you can re-throw the exception with a
user friendly message.

Example of rethrowing exception
<?php
class exc extends Exception {} catch (exc $e)
class test {
{ echo $e->getMessage();
public function testing() }
{
}
try };
{ $ob= new test;
try $ob->testing();
{ ?>
throw new Exc("PHP
exception handling");
}
catch (Exc $e)
{ re-throw an exception
throw $e;
}
}

Set a top level
exception handler


Concept of top level exception handler
The set_exception_handler() function sets a user-defined
function to handle all uncaught exceptions.

<?php
function customError($errno, $errstr)
{
echo "<b>Error:</b> [$errno] $errstr";
}
set_error_handler("customError");
echo($test);
?>


Rules for exception
• Code may be surrounded in a try block, to help
catch potential exceptions
• Each try block or "throw" must have at least one
corresponding catch block
• Multiple catch blocks can be used to catch
different classes of exceptions
• Exceptions can be thrown (or re-thrown) in a catch
block within a try block

A simple rule: If you throw something, you have to catch it.


5.4
Not meeting conditions


Concept of not meeting condition

• Error trapping can not catch all problems in your
code. It will catch only problems related to PHP
itself.

• Any problem you are having with conditions it your
code will not be caught by simple error traping.

• You will have to do this manually, by using several
different methods of troubleshooting in your code.


Concept of not meeting condition
Some common problems are:

• IF statement block not getting executed:
While you are submitting a form, you are checking
whether or not the submit button has
been pressed.

• Variable values are not getting displayed:
Another common problem occurs when variables
are not being output. Mostly variables are just fine
but the programmer can not figure out why they are
not being output.


5.5
Parse error


Concept of parse error
• It occurs when
• you forget a semicolon,
• Curly braces are mismatched,
• square brackets are not used properly.

• These parse errors usually don’t have to do with a
condition statement, they are mainly syntax error
that will cause the script to halt execution.

•Parse error are worst error than fatal error because
they will not let the script run at all, they merely
give you the error information.


Summary

• Error types in PHP

• Generating PHP errors

• Exceptions

• Not meeting conditions

• Parse errors


Chapter - 6

Images with PHP

Images with PHP

6.1 working with GD library

6.2 File types with GD and PHP

6.3 Compiling PHP with GD

6.4 Creating the image table

6.5 uploading the image


6.1
Working with GD
library


What is GD library?
• GD stands for “Graphics Draw”.

• GD is an open source code library for the dynamic
creation of images by programmers. GD creates
PNG, JPEG and GIF images, among other formats.

• GD is commonly used to generate charts, graphics,
thumbnails, and most anything else, on the fly.

• While not restricted to use on the web, the most
common applications of GD involve web site
development.

What is GD library? Conti…
• If you have the GD library (available at
http://www.libgd.org/) you will also be able to create
and manipulate images.
• The format of images you are able to manipulate
depend on the version of GD you install, and any
other libraries GD might need to access those
image formats.
• Versions of GD older than gd-1.6 support GIF
format images, and do not support PNG, where
versions greater than gd-1.6 and less than gd-2.0.28
support PNG, not GIF. GIF support was re-enabled
in gd-2.0.28.

6.2
Files types in GD
and PHP


Supported image formats
Image
Notes
format
Only supported in GD versions older than gd-1.6 and
newer than gd-2.0.28. Read-only GIF support is available
gif
with PHP 4.3.0 and the bundled GD-library. Write support
is available since PHP 4.3.9 and PHP 5.0.1.
When building the jpeg library (prior to building PHP)
you must use the --enable-shared option in the
jpeg configure step. If you do not, you will receive an error
saying libjpeg.(a|so) not found when you get to the
configure step of building PHP.

png Only supported in GD versions greater than gd-1.6.

It's likely you have this library already available, if your
xpm
system has an installed X-Environment.

6.3
Compiling PHP with
GD


Enabling GD in PHP
• In windows, first make sure the php_gd.dll file is
in the ext folder within the PHP installation’s
directory.
• e.g. if PHP is installed in C:, then look in
C:PHPext and find following line in php.ini file:
;extension=phpgd2.dll
• Remove the leading semicolon to uncomment it,
save the change and restart Apache.
• To test GD installation, run the following code:
<?php
print_r(gd_info());
?>

Image functions
• ImageCreate ($width, $height) - creates an image
handle/object of specified width and height.
• ImageColorAllocate ($handle, $R, $G, $B) – set the
background color of handle with specified amount
of RGB. The value of RGB must be between 0 – 255.
• ImageString ($handle, $font, $x,&y,“text“,$txt_color)
enter the text in graphics. Font must be of 1-5.
• ImagePng ($handle) – creates PNG image.
• ImageTTFText($h,$size,$rotation,$x,$y,$color,
$font,$text) – allows to choose fonts which is in
TTF format


Creating Rectangle with text
Set content type to png/jpeg/gif
<?php
header ("Content-type: image/png");
$handle = ImageCreate (130, 50) or die ("Cannot Create image");
$bg_color = ImageColorAllocate ($handle, 255, 0, 0);
$txt_color = ImageColorAllocate ($handle, 0, 0, 0);
ImageString ($handle, 5, 5, 18, "This is PHP image", $txt_color);
ImagePng ($handle);
?>


Working with fonts
<?php
header ("Content-type: image/gif");
ImageTTFText ($handle, 20, 15, 30, 40, $txt_color,
"C:/Windows/Fonts/Verdana.ttf", "PHP");
ImageGif ($handle);
?>


Drawing Lines
<?php header ("Content-type: image/png");
$line_color = ImageColorAllocate ($handle, 0, 0, 0);
ImageLine($handle, 65,0, 530, 150, $line_color);
ImageString ($handle, 5, 5, 18, "PHP", $txt_color);
ImagePng ($handle);
?>


Drawing Lines with loops
<?php
for($i=0;$i<=1300;$i=$i+10)
{
ImageLine($handle, 550, 0, $i, 550, $line_color);
}
ImageString ($handle, 5, 5, 18, "PHP", $txt_color);
ImagePng ($handle);
?>


Drawing an ellipse
<?php
imageellipse ($handle, 650, 275, 1000, 400, $line_color);
ImageString ($handle, 5, 5, 18, "PHP.About.com", $txt_color);
ImagePng ($handle);
?>


Drawing an ellipse with fill
<?php
imagefilledellipse ($handle, 650, 225, 500, 200, $line_color);
ImageString ($handle, 5, 5, 18, "PHP.About.com", $txt_color);
ImagePng ($handle);
?>


Arcs & Pies
<?
header('Content-type: image/png');
$handle = imagecreate(1000, 1000);
$background = imagecolorallocate($handle, 255,0, 0);
$red = imagecolorallocate($handle, 255, 0, 0);
$green = imagecolorallocate($handle, 0, 255, 0);
$blue = imagecolorallocate($handle, 0, 0, 255);
imagefilledarc($handle, 50, 50, 100, 50, 0, 90,$red, IMG_ARC_PIE);
imagefilledarc($handle, 50, 50, 100, 50, 90, 225,$blue, IMG_ARC_PIE);
imagefilledarc($handle, 50, 50, 100, 50, 225, 360,$green,IMG_ARC_PIE);
imagepng($handle);
?>


Arcs & Chords
<?php
$h = ImageCreate(100, 100);
$bg = ImageColorAllocate($h, 255,255, 255);
$r = ImageColorAllocate($h, 255, 0, 0);
$g = ImageColorAllocate($h, 0, 255, 0);
$b = ImageColorAllocate($h, 0, 0, 255);
Imagefilledarc($h,50,50,100,50,0,90,$r,IMG_ARC_CHORD);
Imagefilledarc($h,50,50,100,50,90,225,$b,IMG_ARC_CHORD);
Imagefilledarc($h,50,50,100,50,225,360,$g,IMG_ARC_CHORD);
ImagePng($h);
?>


Arcs & No fill
<?php
Imagefilledarc($h,50,50,100,50,0,90,$r,IMG_ARC_NOFILL);
Imagefilledarc($h,50,50,100,50,90,225,$b,IMG_ARC_NOFILL);
Imagefilledarc($h,50,50,100,50,225,360,$g,IMG_ARC_NOFILL);
ImagePng($h);
?>


Arcs & edged
<?php
Imagefilledarc($h,50,50,100,50,0,90,$r,IMG_ARC_EDGED);
Imagefilledarc($h,50,50,100,50,90,225,$b,IMG_ARC_EDGED);
Imagefilledarc($h,50,50,100,50,225,360,$g,IMG_ARC_EDGED);
ImagePng($h);
?>


Manipulating images
With PHP


Manipulating images
To begin any manipulation, one must access an
image resource.
• imagecreate($width, $height) – creates a blank
image resource of the specified size.
• imagecreatefromgif($filename) – creates an image
resource from the specified GIF format file.
• imagecreatefromjpeg($filename) – creates an image
resource from the specified JPEG format file.
• imagecreatefromPNG($filename) – creates an image
resource from the specified PNG format file.

All of these functions return ‘resources’ which are
used in GD library.

6.4
Creating image table


Image table
• To store images in database, large BLOB is a
suitable format, provided in MySQL.

• Example:

CREATE TABLE ‘images’(‘imageID’ INT(10) NOT
NULL AUTO INCREMENT, ‘imagedata’ LONGBLOB
NOT NULL, PRIMARY KEY (‘imageID’));


6.5
Uploading image


Upload_form.php

<html><body>
<form action="upload_file.php" method="post"
enctype="multipart/form-data">
<label>Filename:</label>
<input type="file" name="file" id="file" />
<input type="submit" name="submit" value="Upload" />
</form>
</body></html>


Upload_img.php Connect to mysql server

<?php
$link=mysql_connect("localhost","root","");
if(!$link)
{
die('Not connected:'.mysql_error());
}
$db=mysql_select_db('upload',$link);
if(!$db)
{ Connect to database server

die('Database error:‘.mysql_error());
}


Upload_img.php
$max="1000000";
$img_array=array("image/jpeg","image/jpg","image/gif","image/bmp","imag
e/png");
$file=$_FILES['file']['type'];
//if submit is clicked
if(@$_POST['submit'])
{
//check for the image type before uploading
if(in_array($file,$img_array))
{
//check whether the file is uploaded
if(is_uploaded_file($_FILES['file']['tmp_name']))
{
//check whether the file size is below 1MB
if($_FILES['file']['size']<$max)
{
//reading image data
$imgdata=addslashes(file_get_contents($_FILES['file']['tmp_name']));

Upload_img.php
//insert into database
$sql="insert into image(imgdata) values($imgdata)";
mysql_query($sql,$link) or die(mysql_error());
$msg="Database successfully updated";
}
else
{
$msg="file size exceed";
}
}
}
else
{
$msg="not valid image";
}}?>

Summary

• Working with GD library

• File types with GD and PHP

• Compiling PHP with GD

• Creating the image table

• Uploading the image


Chapter - 7
Introduction to
MySQL

7 Introduction to MySQL

7.1 MySQL structure and syntax
7.2 Types of MySQL tables and storage engine
7.3 MySQL commands
7.4 Integration of PHP with MySQL
7.5 Connection to the MySQL server
7.6 Working with PHP and arrays of data
7.7 Referencing two tables
7.8 Joining two tables


7.1
MySQL structure
and syntax


What is Database?
• A database is a collection of information that is
organized so that it can easily be accessed,
managed, and updated.
• In computing, databases are sometimes classified
according to their organizational approach.
•The most prevalent approach is the relational
database, a tabular database in which data is
defined so that it can be reorganized and accessed
in a number of different ways.
• In RDBMS the data is stored in different tables and
relations are established using primary keys and
foreign keys.

What is Database? Conti…
• A RDBMS is software that:
• Enables you to implement a database with tables,
columns and indices.
• Guarantees the referential integrity between rows
of various tables.
• Update the indices automatically.
• Interprets an SQL query.


RDBMS Terminology
Before we proceed to explain MySQL database
system, lets revise few definitions related to
database.

• Database: A database is a collection of tables,
with related data.

• Table: A table is a matrix with data. A table in a
database looks like a simple spreadsheet.

• Column: One column (data element) contains data
of one and the same kind, for example the
column ID.

RDBMS Terminology conti…
• Row: A row (= tuple, entry or record) is a group of
related data, for example the data of one
subscription.

• Redundancy: Storing data twice, redundantly to
make the system faster.

• Primary Key: A primary key is unique. A key value
can not occur twice in one table. With
a key you can find at most one row.

• Foreign Key: A foreign key is the linking pin
between two tables.

RDBMS Terminology conti…
• Compound Key: A compound key (composite key)
is a key that consists of multiple
columns, because one column is
not sufficiently unique.

• Index: An index in a database resembles an index
at the back of a book.

• Referential Integrity: Referential Integrity makes
sure that a foreign key value
always points to an existing
row.

Introduction to SQL
• SQL stands for Structured Query Language

• SQL lets you access and manipulate databases

• SQL is an ANSI (American National Standards
Institute) standard

• SQL can execute queries against a database

• SQL can retrieve data from a database

• SQL can insert, update and delete records
in a database

Introduction to SQL conti…
• SQL can create new databases

• SQL can create new tables in a database

• SQL can create stored procedures in a database

• SQL can create views in a database

• SQL can set permissions on tables, procedures,
and views


Introduction to MySQL
MySQL is an open-source database system with
which we can do the following things:

• design the structure of the tables (called schema)
and how they relate to one another
• add, edit and delete data
• sort and manipulate data
• query the database (that is, ask questions about
the data)
• produce listings based on queries


Introduction to MySQL conti…

To interact with MySQL, we enter commands on
a command line. These commands, such as
CREATE, INSERT, UPDATE, etc. are based on a
more general language called SQL (Structured
Query Language).


Uses of MySQL
1. Scalability and Flexibility:
The MySQL database server provides the Ultimate
in scalability, sporting the capacity to handle
deeply embedded applications with a massive
data warehouses holding terabytes of information.
the open source nature of MySQL allows complete
customization for those wanting to add unique
requirements to the database server.
2. High Performance:
A unique storage-engine architecture allows
database professionals to configure the MySQL
database server specifically for particular
applications

Uses of MySQL conti…
3. High Availability
MySQL offers a variety of high-availability
Options from high-speed master/slave replication
configurations, to specialized Cluster servers
offering instant failover, to third party vendors
offering unique high-availability solutions for the
MySQL database server.
4. Robust Transactional Support
MySQL offers one of the most powerful
transactional database engines on the market.
Features include complete ACID (atomic, consistent,
isolated, durable) transaction support,


5. Web and Data Warehouse Strengths
MySQL is the de-facto standard for high-traffic
web sites because of its high-performance query
engine, tremendously fast data insert capability, and
strong support for specialized web functions like
fast full text searches.
6. Strong Data Protection
Because guarding the data assets of
corporations is the number one job of database
professionals, MySQL offers exceptional security
features that ensure absolute data protection.


7. Comprehensive Application Development
One of the reasons MySQL is the world's most
popular open source database is that it provides
comprehensive support for every application
development need. Within the database, support can
be found for stored procedures, triggers, functions,
views, cursors, ANSI-standard SQL, and more.
8. Management Ease
MySQL offers exceptional quick-start capability
with the average time from software download to
installation completion being less than fifteen
minutes. This rule holds true whether the platform
is Microsoft Windows, Linux, Macintosh, or UNIX.

9. Open Source Freedom and 24 x 7 Support
Many corporations are hesitant to fully commit
to open source software because they believe they
can't get the type of support or professional service
safety nets they currently rely on with proprietary
software to ensure the overall success of their key
applications.
10. Lowest Total Cost of Ownership
By migrating current database-drive
applications to MySQL, or using MySQL for new
development projects, corporations are realizing
cost savings that many times stretch into seven
figures.

Features of MySQL
• Relational Database System: MySQL is a relational
database system.
• Client/Server Architecture: MySQL is a client/server
system. There is a database server (MySQL) and
arbitrarily many clients (application programs),
which communicate with the server; that is, they
query data, save changes, etc. The clients can run
on the same computer as the server or on another
computer (communication via a local network or
the Internet).
• SQL compatibility: MySQL supports as its database
language -- as its name suggests – SQL
(Structured Query Language).

Features of MySQL conti..
• User interface: There are a number of convenient
user interfaces for administering a MySQL server.
• Full-text search: Full-text search simplifies and
accelerates the search for words that are located
within a text field.
• Replication: Replication allows the contents of a
database to be copied (replicated) onto a number
of computers.
• Transactions: In the context of a database system,
a transaction means the execution of several
database operations as a block. The database
system ensures that either all of the operations are
correctly executed or none of them.

• Foreign key constraints: These are rules that
ensure that there are no cross references in linked
tables that lead to nowhere. MySQL supports
foreign key constraints for InnoDB tables.
• Programming languages: There are quite a number
of APIs (application programming interfaces) and
libraries for the development of MySQL application.
• ODBC: MySQL supports the ODBC interface
Connector/ODBC. This allows MySQL to be
addressed by all the usual programming languages
that run under Microsoft Windows (Delphi, Visual
Basic, etc.).


• Platform independence: It is not only client
applications that run under a variety of operating
systems; MySQL itself (that is, the server) can be
executed under a number of operating systems.
• Speed: MySQL is considered a very fast database
program. This speed has been backed up by a large
number of benchmark tests


MySQL Architecture


7.2
Types of MySQL tables
and
storage engine

MySQL table types and storage engine
MySQL supports various of table types or storage
engines to allow you to optimize your database.
The table types are available in MySQL are:

• ISAM • BerkeleyDB (BDB)

• MyISAM • MERGE

• InnoDB • HEAP


MySQL table types and storage engine conti..
• The most important feature to make all the table
types above distinction is transaction-safe or not.

• Only InnoDB and BDB tables are transaction safe
and only MyISAM tables support full-text indexing
and searching feature.

• MyISAM is also the default table type when you
create table without declaring which storage
engine to use.


Features of MySQL table types
Here are some major features of each table types:
• ISAM-ISAM had been deprecated and removed from
version 5.x. All of its functionality entire replace by
MyISAM. ISAM table has a hard disk size 4GB and
is not portable.

•MyISAM-MyISAM table type is default when you
create table. MyISAM table work very fast but not
transaction-safe. The size of MyISAM table depends
on the operating system and the data file are
portable from system to system.
With MyISAM table type, you can have 64 keys per
table and maximum key length of 1024 bytes.

Features of MySQL table types conti..
• InnoDB-Different from MyISAM table type, InnoDB
table are transaction safe and supports row-level
locking. Foreign keys are supported in InnoDB
tables. The data file of InnoDB table can be stored
in more than one file so the size of table depends
on the disk space. Like the MyISAM table type,
data file of InnoDB is portable from system to
system. The disadvantage of InnoDB in comparison
with MyISAM is it take more disk space.
• BDB-BDB is similar to InnoDB in transaction safe.
It supports page level locking but data file are not
portable.

Features of MySQL table types conti..

• MERGE-Merge table type is added to treat multiple
MyISAM tables as a single table so it remove the
size limitation from MyISAM tables.

• HEAP-Heap table is stored in memory so it is the
fastest one. Because of storage mechanism, the
data will be lost when the power failure and
sometime it can cause the server run out of
memory. Heap tables do not support columns with
AUTO_INCREMENT, BLOB and TEXT
characteristics.

MySQL
Data Types


MySQL Data Types
MySQL provides you many more specific data types than
just "numeric" or "string". Each data type in MySQL can
be determined by the following characteristics:

• What kind of value it can represent.
• The space values take up and whether the
values are fixed-length or variable-length.
• The values of a data type can be indexed.
• How MySQL compare values of that data
types.


MySQL Data Types conti…
• Numeric Data Types

You can find all SQL standard numeric types in
MySQL including exact number data type and
approximate numeric data types including integer, fixed-
point and floating point. In addtion, MySQL also supports
BIT data type for storing bit field values. Numeric types
can be signed or unsigned except BIT type.


MySQL Data Types (Numeric)
Numeric Types Description
TINYINT A very small integer
SMALLINT A small integer
MEDIUMINT A medium-sized integer
INT A standard integer
BIGINT A large integer
DECIMAL A fixed-point number
A single-precision floating-
FLOAT
point number
A double-precision floating-
DOUBLE
point number
BIT A bit field


• String Data Types

In MySQL, string can hold anything from plain text
to binary data such as images and files. String can be
compared and searched based on pattern matching by
using LIKE clause or regular expression.


MySQL Data Types (String)
String Types Description
CHAR A fixed-length non-binary (character) string
VARCHAR A variable-length non-binary string
BINARY A fixed-length binary string
VARBINARY A variable-length binary string
TINYBLOB A very small BLOB (binary large object)
BLOB A small BLOB
MEDIUMBLOB A medium-sized BLOB
LONGBLOB A large BLOB
TINYTEXT A very small non-binary string
TEXT A small non-binary string
MEDIUMTEXT A medium-sized non-binary string
LONGTEXT A large non-binary string
An enumeration; each column value may be
ENUM
assigned one enumeration member
A set; each column value may be assigned
SET
zero or more set members


• Date and Time Data Types

MySQL provides types for date and time and
combination of date and time. In addition, MySQL also
provide timestamp data type for tracking last change on a
record. If you just want to store the year without date and
month, you can use YEAR data type.


MySQL Data Types (Date and Time)
Date and Time Types Description
A date value in 'CCYY-MM-
DATE
DD' format
A time value in 'hh:mm:ss'
TIME
format
A date and time value in
DATETIME 'CCYY-MM-DD hh:mm:ss'
format
A timestamp value in 'CCYY-
TIMESTAMP
MM-DD hh:mm:ss' format
A year value in CCYY or YY
YEAR
format

7.3
MySQL Commands


MySQL Commands
• CREATE-create databases and tables

• SELECT-select table rows based on certain
conditions

• DELETE- delete one or more rows of a table

• INSERT- insert a new row in a table

• UPDATE- update rows in a table

• ALTER- alter the structure of a table

Commands to login to MySQL console
Click on wampserver -> MySQL -> MySQL console
Enter password

Command line


Login using phpMyAdmin
Click on wampserver -> phpMyAdmin


7.4
Integration of PHP
With MySQL


Integration of PHP with MySQL
To connect to the database one should implement the
following steps:

• Connecting to a Database server
• Create new database
• Select MySQL database
• Fetch and show tables and records of database
• Execute queries though PHP script
• Manipulate records, tables and database
• Error handling
• Closing connection


7.5
Connection to
MySQL server


Connecting to database
• Before you can access data in a database, you must
create a connection to the database.

Syntax:
mysql_connect(servername,username,password);
servername Optional. Specifies the server to connect to.
Default value is "localhost:3306"
username Optional. Specifies the username to log in with.
Default value is the name of the user that owns
the server process
password Optional. Specifies the password to log in with.
Default is ""

Connecting to database example
$con object stores the connectionstring
<?php
$con = mysql_connect("localhost",”root",”");
if (!$con)
{
die('Could not connect: ' . mysql_error());
}
echo “Database connection successed”;
// some code
mysql_close($con); Closing connection
?>


Creating database using PHP script
• To get PHP to execute the statement we must
use the mysql_query() function. This function is
used to send a query or command to a MySQL
connection.
• Syntax:
mysql_query(query, link)

query Required. SQL query to create or delete
database.
link Optional. If not specified last opened connection
will be used


Creating database using PHP script
<?php
$con = mysql_connect("localhost","peter","abc123");
$sql=“CREATE DATABASE sample”;
if (!$con)
{
}
if(mysql_query($sql,$con))
{
echo "Database created";
} Query Connection string
mysql_close($con); Get the query
?>

Selecting database using PHP script
• PHP provides mysql_select_db() function to select
a database. It returns TRUE on success and FALSE
on failure.
• Syntax:

mysql_select_db(db_name, connection)

db_name Required. MySQL database name to be selected
connection Optional. If not specified last opened connection
will be used


Selecting database using PHP script
<?php
if (!$con)
{
}
if(mysql_query("CREATE DATABASE sample",$con))
{
echo "Database created"; Database name
}
Connection string
mysql_select_db(‘sample’,$con);
mysql_close($con);
?>

Drop database using PHP script
<?php
if (!$con)
{
}
if(mysql_query(“DROP DATABASE sample",$con))
{
echo "Database Deleted successfully";
}
mysql_close($con);
?>


7.6
Working with PHP and
Array of data


Working with array of data
• The following functions are used to display
the selected data correctly in PHP which you can
use to retrieve data from MySQL database result
set.
• mysql_fetch_assoc()- fetch a result row in an
associative array.
• mysql_fetch_row()- fetch a result row in an
enumerated array.
• mysql_fetch_array()- fetch a result row in an
associative or numeric or
both array.
The functions returns only one record.

Mysql_fetch_array() function
<?php
$link=mysql_connect(“localhost”,”root”,””);
mysql_select_db($db,$link);
$sql="SELECT name,age FROM persondetail";
$result=mysql_query($sql,$link);
while($rowarray=mysql_fetch_array($result))
{
echo ($rowarray['name']);
echo ($rowarray['age']);
}
mysql_close($link);
?>

Mysql_fetch_array() function conti..


Mysql_fetch_row() function
<?php
$link=mysql_connect(“localhost”,”root”,””);
mysql_select_db($db,$link);
$sql="SELECT name,age FROM persondetail";
$result=mysql_query($sql,$link);
while($rowarray=mysql_fetch_row($result))
{
echo ($rowarray[0]);
echo ($rowarray[1]);
}
mysql_close($link);
?>

Mysql_fetch_row() function


7.7
Referencing two table


Referencing two tables

• To get information from more than one table
reference the individual table in query and link
them temporarily through a common field.

• formally JOIN the individual tables in query.


7.8
Joining two tables


Joining two tables

• One of the great characteristics of SQL is the fact
that one can develop access and modify data
across various table.

• A join command unites some or all of the data
from two or more tables into one set. The joining
capability allows creating small, compact
relational tables that can influence database
performance.


Joining two tables

• One can use one of the following JOINS:

• Cross join
• Equi-Join
• Non equi join
• The right join
• The full join
• Self join


Summary

• MySQL structure and syntax
• Types of MySQL tables and storage engine
• MySQL commands
• Integration of PHP with MySQL
• Connection to the MySQL server
• Working with PHP and arrays of data
• Referencing two tables
• Joining two tables


Chapter - 8
Working with
database

Working with database
8.1 Creating a table
8.2 Manipulating the table
8.2.1 Filling the table with data
8.2.2 Adding links to the table
8.2.3 Adding data the table
8.2.4 Displaying information
8.2.5 Displaying the movie detail
8.3 Editing the database
8.4 Inserting record
8.5 Deleting record
8.6 Editing data

8.1
Creating table


Creating database
Click on WAMPSERVER->localhost

WAMPSERVER in
Quick launch bar


Creating database

List of database Write database
name here and
click on create

Creating table

List of database Write table name
And no. of field
here and click on Go

Creating fields

Write field
name
And its
attributes
here and click
on save or Go


Inserting values

Click insert tab, Insert values here
and click on Go


Displaying records

Query executed

Display inserted record


Creating database
And
Table Using PHP


Creating database using PHP
<?php
$con = mysql_connect("localhost","root“,””);
if (!$con)
{
}
if (mysql_query("CREATE DATABASE my_db",$con))
{
}
else Create database

{
echo "Error creating database: " mysql_error();

Creating table using PHP
<?php
$con = mysql_connect("localhost","root");
if (!$con)
{
}
if (mysql_query("CREATE DATABASE my_db",$con))
{
} Create table
else
{
echo "Error creating database: " . mysql_error();
}
mysql_select_db("my_db", $con);
$sql = "CREATE TABLE Persons
(FirstName varchar(15),LastName varchar(15),Age int)";
mysql_query($sql,$con);
mysql_close($con);?> Developed By: Amit Lakhani, TFGP Adipur

8.2
Manipulating the
table


Manipulating table
• We can perform various operations on table like:

• Inserting record

• Deleting record

• Updating data

• Searching record


Inserting records
<?php
if (!$con)
{
} Insert record
mysql_query("INSERT INTO Persons (FirstName, LastName,
Age) VALUES ('Peter', 'Griffin', '35')");
mysql_query("INSERT INTO Persons (FirstName, LastName,
Age) VALUES ('Glenn', 'Quagmire', '33')");
echo"Data added successfully<br>";
$numrows=mysql_affected_rows($con);
echo "Numbers of rows affected:".$numrows;
mysql_close($con);

Deleting record
<?php
if (!$con)
{
} delete record
mysql_query("DELETE FROM Persons WHERE
LastName='Griffin'");
echo "Data deleted successfully<br>";
mysql_close($con);

8.2.1
Filling/Inserting
data using forms


Filling data using forms


Mysql_form_input.php
Filling data using forms code is called when button
is clicked
<html><body>
<form action=“mysql_form_input.php" method="post" >
<table><tr><td>Roll No:</td><td><input type="text"
name="rollno" /></td></tr>
<tr><td>Name:</td><td><input type="text" name="name"
/></td></tr>
<tr><td>Address:</td><td><textarea name="add">
</textarea></td></tr>
<tr><td>Contact_No: </td><td><input type="text"
name="phone" /></td></tr>
<tr><td colspan="2" align="center"><input type="submit"
value="Submit“ name="btnsave" /></td></tr>
</form></body>
</html> Developed By: Amit Lakhani, TFGP Adipur

Insert data using forms
<?php mysql_form_input.php
if($_POST['btn']=="Save")
{
$con = mysql_connect("localhost","root","");
if ($con)
{ Data is inserted in table
mysql_select_db("student_info", $con);
$rollno=$_POST['rollno'];
$name=$_POST['name'];
$address=$_POST['add'];
$phoneno=$_POST['phone'];
$sql="INSERT INTO stu_entry (Roll_no,Name,Address,phone_no)VALUES
('$rollno','$name','$address','$phoneno')";
if(mysql_query($sql,$con))
{
echo"Data added successfully<br>";
}
else
{die("could not insert:".mysql_error());}
mysql_close($con);}} Developed By: Amit Lakhani, TFGP Adipur

Insert data using forms output

Enter records

Press submit

Inserts one record to
database


8.2.2
Adding links to the
table


Display records as links
<?php mysql_table_link.php
if ($con)
{
mysql_select_db("student_info", $con); Creates link to
$result=mysql_query("SELECT * FROM stu_entry "); Table_detail_link.php
echo "Click to get details";
if(mysql_num_rows($result)>0)
{
echo "<table border=1>
<tr><th>Rollno</th></tr>";
while($row=mysql_fetch_row($result))
{
echo "<tr>";
echo "<td><a href="table_detail_link.php? id={$row
[0]}">" .$row[0]."</a></td>";
echo "</tr>";
}
echo "</table>";
}
mysql_close($con);

Display records as links conti..
<?php
Table_detail_link.php
if ($con)
{ Select linked field
$rno=$_REQUEST['id'];
$result=mysql_query("SELECT * FROM stu_entry WHERE Roll_no LIKE '%$rno'");
<tr><th>Rollno</th><th>Name</th><th>Address</th><th>Contact_No</th></tr>";
{
echo "<tr>"; Displays clicked record
echo "<td>" .$row[0]."</td>";
echo "<td>" .$row[1]."</td>";
echo "<td>" .$row[2]."</td>";
echo "<td>" .$row[3]."</td>";
echo "</tr>";
}
echo "</table>";
}
mysql_close($con);

Display record as links output
Click on the link
And it will display
Clicked record


8.2.3
Adding to the table


8.2.4
Display new
information


Display data using forms
if($_POST['btn']=="Display") mysql_form_input.php
{
if ($con)
{
$result=mysql_query("SELECT * FROM stu_entry");
<tr><th>Roll no</th><th>Name</th> <th>Address</th><th>Contact_No</th></tr>"
{
echo "<tr>"; Data is selected and
echo "<td>" .$row[0]."</td>"; Displayed in table
echo "<td>" .$row[1]."</td>";
echo "<td>" .$row[2]."</td>";
echo "<td>" .$row[3]."</td>";
echo "</tr>";
}
echo "</table>";
mysql_close($con);
}

Display data using forms

Display all records
When display is
clicked


Searching data
using forms


Searching data using forms
if($_POST['rollno']==$rollno)
<?php {
if($_POST['btn']=="Search") $result=mysql_query("SELECT * FROM stu_entry
{ WHERE Roll_no LIKE '%$rollno'");
$con = mysql_connect("localhost", if(mysql_num_rows($result)>0)
"root",""); {
if ($con) echo "<table border=1>
{ <tr><th>Roll no</th><th>Name</th>
mysql_select_db("student_info", <th>Address</th> <th>Contact_No</th></tr>";
$con); while($row=mysql_fetch_row($result))
$rollno=$_POST['rollno']; {
$name=$_POST['name']; echo "<tr>";
$address=$_POST['add']; echo "<td>" .$row[0]."</td>";
$phoneno=$_POST['phone']; echo "<td>" .$row[1]."</td>";
echo "<td>" .$row[2]."</td>";
echo "<td>" .$row[3]."</td>";
Data is selected and echo "</tr>";
Displayed in table }
echo "</table>“;
}

Search data using forms output
Enter roll no. to search

Press search

It displays selected
record


8.3
Edit the database


Edit records from the table


Edit records from the table
<?php
Mysql_edit.php
if ($con)
{
$result=mysql_query("SELECT * FROM stu_entry ");
echo "Click to Edit details";
{
<tr><th>Rollno</th><th>Name</th> <th>Address</th>
<th>Phone_no</th> </tr>";
{
echo "<tr>";
echo "<td><a href="mysql_edit_detail.php? id={$row
[0]}">" .$row[0]."</a></td>";
echo "<td>" .$row[1]."</td>";
echo "<td>" .$row[2]."</td>";
echo "<td>" .$row[3]."</td>";
echo "</tr>";
}echo "</table>“;mysql_close($con);}?>

Edit records from the table conti..
Mysql_edit.php

Click on the link
And it will display
Clicked record on
Other page


<?php Mysql_edit_detail.php
if ($con)
{
$rno=$_REQUEST['id'];
$result=mysql_query("SELECT * FROM stu_entry WHERE Roll_no LIKE '%$rno'");
while($row=mysql_fetch_row($result));
{
echo "<form action="mysql_save_detail.php" method="post">";
echo “Roll No:<input type="text" name="rollno" value={$row[0]}>";
echo “Name:<input type="text" name="name" value={$row[1]}>";
echo “Address:<textarea name="add" rows="5" cols="20">" .$row[2].
"</textarea>";
echo “Phone No:<input type="text" name="phoneno" value={$row[3]}>";
echo “<input type="submit" name="btn" value="Save“>";
echo "</form>";
}
}mysql_close($con);

Mysql_edit_detail.php

update with new Entries and
click on Save button and form
will call mysql_save_detail.php
page


<?php Mysql_save_detail.php
if(isset($_POST['btn']))
{
if ($con)
{
$rno=$_POST['rollno'];
$name=$_POST['name'];
$add=$_POST['add'];
$phno=$_POST['phoneno'];
$update= "UPDATE stu_entry SET Roll_no='$rno', Name='$name', Address=
'$add', phone_no='$phno' WHERE Roll_no LIKE '%$rno%'";
if(mysql_query($update,$con))
{
echo "Records updated successfully";
}
mysql_close($con);
}}

8.4
Inserting record


8.5
Delete records
from the table


Delete records from the table


Delete records from the table conti..
<?php
Mysql_delete.php
if ($con)
{
$result=mysql_query("SELECT * FROM stu_entry ");
echo "Click to Delete Records";
{
<tr><th>Rollno</th><th>Name</th> <th>Address</th> <th>Phone_no</th> </tr>";
{
echo "<tr>";
echo "<td><a href="delete_record.php? id={$row[0]}">"
.$row*0+."</a></td>“;
echo "<td>" .$row[1]."</td>";
echo "<td>" .$row[2]."</td>";
echo "<td>" .$row[3]."</td>";
echo "</tr>";
}

Mysql_delete.php

echo "<td colspan=4><a href="delete_record.php?id=All">Delete
All</a></td>";
echo "</tr>";
echo "</table>";
}
else
{
echo "<br>Table is empty";
}

mysql_close($con);
}

?>


<?php Delete_record.php
if ($con)
{
$deletereq=$_REQUEST['id'];
if($deletereq=="All")
{
$delete="DELETE FROM stu_entry";
}
else
{
$delete="DELETE FROM stu_entry WHERE Roll_no LIKE '%$deletereq%'";
}
if(mysql_query($delete, $con))
{
echo "Record(s) deleted successfully";
}
mysql_close($con);
}

Summary

• Creating a table
• Manipulating the table
• Filling the table with data
• Adding links to the table
• Adding data the table
• Displaying information
• Displaying the movie detail
• Editing the database
• Inserting record
• Deleting record
• Editing data

PHP Presentation

In this document

More Related Content

What's hot

Viewers also liked

Similar to PHP Presentation

More from JIGAR MAKHIJA

Recently uploaded

PHP Presentation