http://www.bu.edu.eg/staff/mloey PHP Comprehensive Overview

1. PHP
MOHAMED LOEY

2. Agenda
 Part I: Introduction
 Part II: PHP Syntax
 Part III: PHP Form Handling

3. Agenda
 Part I: Introduction
 What is PHP?
 Why we use PHP?
 PHP Can
 Set Up PHP on Your Own PC

4. What is PHP?
 PHP is a server scripting language, and
is a powerful tool for making dynamic
and interactive Web pages quickly.
 PHP is a widely-used, open source
scripting language
 PHP scripts are executed on the server
 PHP costs nothing, it is free to
download and use

5. Why we use PHP?
 PHP runs on various platforms (Windows, Linux,
Unix, Mac OS X, etc.)
 PHP is compatible with almost all servers used
today (Apache, IIS, etc.)
 PHP supports a wide range of databases
 PHP is easy to learn and runs efficiently on the
server side
 It is powerful enough to be at the core of the
biggest blogging system on the web
(WordPress)!
 It is deep enough to run the largest social
network (Facebook)!

6. PHP Can
 Generate dynamic page content
 Create, open, read, write, delete, and
close files on the server
 Send and receive cookies
 Add, delete, modify data in your
database
 Encrypt data
 Output images, PDF files, and even
Flash movies

7. Set Up PHP on Your Own PC
 Install a web server (Apache)
 Install PHP
 Install a database, such as MySQL
 Example: XAMPP (Apache + MySQL +
PHP + Perl)
 XAMPP is the most popular PHP
development environment

8. Agenda
 Part II: PHP Syntax
 PHP Syntax
 Comments in PHP
 PHP Case Sensitivity
 PHP Variables
 PHP echo and print Statements
 PHP Operators
 PHP Conditional Statements
 PHP Loops
 PHP Functions
 PHP Arrays

9. PHP Syntax
 PHP script can be placed anywhere in
the document.
 A PHP script starts with <?php and
ends with ?>
 The default file extension for PHP files
is ".php".

10. Simple PHP Code

11. Comments in PHP
 A comment in PHP code is a line that is
not read/executed as part of the
program.
 PHP supports three ways of
commenting:

12. PHP Case Sensitivity
 In PHP, all user-defined functions,
classes, and keywords (e.g. if, else,
while, echo, etc.) are NOT case-
sensitive.
 Example:

13. PHP Case Sensitivity
 However; in PHP, all variables are case-
sensitive.
 $color, $COLOR, and $coLOR are
treated as three different variables
 Example:

14. PHP Variables
 Variables are "containers" for storing
information.
 A variable starts with the $ sign, followed by
the name of the variable
 A variable name must start with a letter or
the underscore character
 A variable name cannot start with a number
 A variable name can only contain alpha-
numeric characters and underscores (A-z, 0-9,
and _ )
 Variable names are case sensitive ($y and $Y
are two different variables)

15. PHP Variables
 PHP has no command for declaring a variable.
 Example:

16. PHP echo and print Statements
 In PHP there are two basic ways to get output:
echo and print.
 There are some differences between echo and
print:
 echo - can output one or more strings
 print - can only output one string, and returns always
1
 Example:

17. PHP Operators
 PHP Arithmetic Operators

18. PHP Operators
 PHP Arithmetic Operators Example:

19. PHP Operators
 PHP Assignment Operators

20. PHP Operators
 PHP Assignment Operators Example:

21. PHP Operators
 PHP String Operators

22. PHP Operators
 PHP String Operators Example:

23. PHP Operators
 PHP Increment / Decrement Operators

24. PHP Operators
 PHP Increment / Decrement Operators
Example:

25. PHP Operators
 PHP Comparison Operators

26. PHP Operators
 PHP Comparison Operators Example:

27. PHP Operators
 PHP Logical Operators

28. PHP Operators
 PHP Array Operators

29. PHP Operators
 PHP Array Operators Example:

30. PHP Conditional Statements
 In PHP we have the following conditional
statements:
 if statement - executes some code only if a specified
condition is true
 if...else statement - executes some code if a
condition is true and another code if the condition is
false
 if...elseif....else statement - selects one of several
blocks of code to be executed
 switch statement - selects one of many blocks of
code to be executed

31. PHP Conditional Statements
 If else Example:

32. PHP Conditional Statements
 Switch example:

33. PHP Loops
 In PHP, we have the following looping
statements:
 while - loops through a block of code as long as the
specified condition is true
 do...while - loops through a block of code once, and
then repeats the loop as long as the specified
condition is true
 for - loops through a block of code a specified
number of times
 foreach - loops through a block of code for each
element in an array

34. PHP Loops
 PHP while Loop example:

35. PHP Loops
 PHP do...while Loop example:

36. PHP Loops
 PHP for Loop example:

37. PHP Loops
 PHP foreach Loop example:

38. PHP Functions
 A function is a block of statements that can be
used repeatedly in a program.
 A function will not execute immediately when a
page loads.
 A function will be executed by a call to the
function.

39. PHP Functions
 PHP function examples:

40. PHP Arrays
 An array is a special variable, which can hold
more than one value at a time.
 Example:

41. PHP Associative Arrays
 Associative arrays are arrays that use named
keys that you assign to them.
 Example:

42. PHP Sorting Arrays
 PHP array sort functions:
 sort() - sort arrays in ascending order
 rsort() - sort arrays in descending order
 asort() - sort associative arrays in ascending order,
according to the value
 ksort() - sort associative arrays in ascending order,
according to the key
 arsort() - sort associative arrays in descending order,
according to the value
 krsort() - sort associative arrays in descending order,
according to the key

43. Agenda
 Part III: PHP Form Handling
 PHP GET vs. POST
 PHP $_GET
 PHP $_POST

44. PHP Form Handling
 One of the most powerful features of PHP is
the way it handles HTML forms. The basic
concept that is important to understand is
that any form element will automatically be
available to your PHP scripts.
 The PHP $_GET and $_POST are used to
collect form-data.

45. PHP GET vs. POST
 Both GET and POST create an array (e.g. array( key
=> value, key2 => value2, key3 => value3, ...)). This
array holds key/value pairs, where keys are the
names of the form controls and values are the input
data from the user.
 When to use GET?
 Information sent from a form with the GET method
is visible to everyone
 facebook.com?welcome.php?name=Mohamed
 When to use POST?
 Information sent from a form with the POST
method is invisible to others
 facebook.com?welcome.php

46. PHP $_GET
 Example:

47. PHP $_GET
 When the user fills out the form above and
clicks the submit button, the form data is sent
for processing to a PHP file named
"welcome.php".
 welcome.php

48. PHP $_GET
 Result:
 Welocome.php Output

49. PHP $_POST
 Example:

50. PHP $_POST
 When the user fills out the form above and
clicks the submit button, the form data is sent
for processing to a PHP file named
"welcome.php".
 welcome.php

51. PHP $_POST
 Result:
 Welocome.php Output

52. THANK U