PHP (BASICS)
• PHP Defination
• PHP Syntax
• PHP Comments
• PHPVariables
• ECHO and PRINT
• PHP Datatypes
• PHP Constents
• PHP Operators
P H P
• PHP is a server scripting language, and a powerful tool for making
dynamic and interactive Web pages.
What is PHP?
• PHP is an acronym for "PHP: Hypertext Preprocessor"
• PHP is a widely-used, open source scripting language
• PHP scripts are executed on the server
• PHP is free to download and use
What is a PHP File?
• PHP files have extension ".php"
WHAT CAN PHP DO?
• PHP can generate dynamic page content
• PHP can create, open, read, write, delete, and close files on the server
• PHP can collect form data
• PHP can send and receive cookies
• PHP can add, delete, modify data in your database
• PHP can be used to control user-access
• PHP can encrypt data
P H P S Y N T A X P H P C O M M E N T S
<html>
<body>
<h1>My first PHP page</h1>
<?php
echo "Hello World!";
?>
</body>
</html>
// Outputs a welcome message:
echo "Welcome Home!";
Multi-line Comments
Multi-line comments start with /* and end with */.
Any text between /* and */ will be ignored.
PHP VARIABLES
• 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
• Variable names are case-sensitive
Example- $x = 5;
$y = "John"
P H P VA R I A B L E S S C O P E
The scope of a variable is the part of the script where the variable can be referenced/used.
PHP has three different variable scopes:
• local
• global
• static
GLOBAL AND LOCAL SCOPE
• A variable declared outside a function has a GLOBAL SCOPE and can only be accessed outside
a function.
Global Scope
<?php
$x = 5; // global scope
function myTest() {
// using x inside this function will generate an error
echo "<p>Variable x inside function is: $x</p>";
}
myTest();
echo "<p>Variable x outside function is: $x</p>";
?>
Output - Variable x inside function is:
Variable x outside function is: 5
LOCAL SCOPE
<?php
function myTest() {
$x = 5; // local scope
echo "<p>Variable x inside function is: $x</p>";
}
myTest();
// using x outside the function will generate an error
echo "<p>Variable x outside function is: $x</p>";
?>
Output - Variable x inside function is: 5
Variable x outside function is:
P H P E C H O A N D P R I N T S T A T E M E N T S
echo and print are more or less the same.They are both used to output data to the screen.
• The differences are small: echo has no return value while print has a return value of 1 so it can be
used in expressions.
• echo can take multiple parameters (although such usage is rare) while print can take one
argument. echo is marginally faster than print.
P H P D A T A T Y P E S
Variables can store data of different types, and different data types can do different
things.
PHP supports the following data types:
• String
• Integer
• Float (floating point numbers - also called double)
• Boolean
• Array
• NULL
P H P S T R I N G
A string is a sequence of characters, like "Hello world!“.
<?php
$x = "Hello world!";
$y = 'Hello world!';
var_dump($x);
echo "<br>";
var_dump($y);
?>
Output - string(12) "Hello world!"
string(12) "Hello world!"
P H P I N T E G E R
• An integer must have at least one digit
• An integer must not have a decimal point
• An integer can be either positive or negative
• Integers can be specified in: decimal (base 10), hexadecimal (base 16), octal (base 8), or binary
(base 2) notation
<?php
$x = 5985;
var_dump($x);
?>
Output - int(5985)
PHP FLOAT
• A float (floating point number) is a number with a decimal point or a number in exponential form.
• In the following example $x is a float.The PHP var_dump() function returns the data type and
value:
<?php
$x = 10.365;
var_dump($x);
?>
Output - float(10.365)
PHP BOOLEAN
A Boolean represents two possible states:TRUE or FALSE.
<html>
<body>
<?php
$x = true;
var_dump($x);
?>
</body>
</html>
Output - bool(true)
P H P A R R A Y
• An array stores multiple values in one single variable.
• In the following example $cars is an array.The PHP var_dump() function returns the data type
and value:
<?php
$cars = array("BMW","Toyota");
var_dump($cars);
?>
Output –
array(2) { [0]=> string(3) "BMW" [1]=> string(6) "Toyota" }
P H P C A S T I N G
Change DataType
Casting in PHP is done with these statements:
(string) - Converts to data type String
(int) - Converts to data type Integer
(float) - Converts to data type Float
(bool) - Converts to data type Boolean
(array) - Converts to data type Array
(object) - Converts to data type Object
(unset) - Converts to data type NULL
<?php
$a="first step";
$b="2";
$c="true";
$d="3.89";
$f="null";
$a= (string) $a;
$b= (array) $b;
$c= (bool) $c;
$d= (float) $d;
$f= (string) $f;
//To verify the type of any object in PHP, use
the var_dump() funtion:
var_du($a);
echo"<br>";
var_dump($b);
echo"<br>";
var_dump($c);
echo"<br>";
var_dump($d);
echo"<br>";
var_dump($f);
?>
OUTPUT :
string(10) "first step"
array(1) { [0]=> string(1) "2" }
bool(true)
float(3.89)
string(4) "null"
P H P C O N S T A N T S
• Constants are like variables, except that once they are defined they cannot be
changed or undefined.
• A constant is an identifier (name) for a simple value. The value cannot be changed
during the script.
• A valid constant name starts with a letter or underscore (no $ sign before the constant
name)
Syntax:
define(name, value, case-insensitive);
P H P O P E R ATO R S
Operators are used to perform operations on variables and values.
PHP divides the operators in the following groups:
• Arithmetic operators
• Assignment operators
• Comparison operators
• Increment/Decrement operators
• Logical operators
• String operators
• Array operators
• Conditional assignment operators
PHP ARITHMETIC OPERATORS
The PHP arithmetic operators are used with numeric values to perform common
arithmetical operations, such as addition, subtraction, multiplication etc.
Operator Name Example Result
+ Addition $x + $y Sum of $x and $y
- Subtraction $x - $y Difference of $x and $y
* Multiplication $x * $y Product of $x and $y
/ Division $x / $y Quotient of $x and $y
% Modulus $x % $y Remainder of $x divided by $y
** Exponentiation $x ** $y Result of raising $x to the $y'th power
P H P A S S I G N M E N T O P E R AT O R S
The PHP assignment operators are used with numeric values to write a value to
a variable
Assignment Same as... Description
x = y x = y The left operand gets set to the value of the expression on the
right
x += y x = x + y Addition
x -= y x = x - y Subtraction
x *= y x = x * y Multiplication
x /= y x = x / y Division
x %= y x = x % y Modulus
P H P C O M PA R I S O N O P E R ATO R S
The PHP comparison operators are used to compare two values (number or string):
Operator Name Example Result
== Equal $x == $y Returns true if $x is equal to $y
=== Identical $x === $y Returns true if $x is equal to $y, and they are of the same
type
!= Not equal $x != $y Returns true if $x is not equal to $y
<> Not equal $x <> $y Returns true if $x is not equal to $y
!== Not identical $x !== $y Returns true if $x is not equal to $y, or they are not of the
same type
> Greater than $x > $y Returns true if $x is greater than $y
< Less than $x < $y Returns true if $x is less than $y
>= Greater than or equal to $x >= $y Returns true if $x is greater than or equal to $y
<= Less than or equal to $x <= $y Returns true if $x is less than or equal to $y
<=> Spaceship $x <=> $y Returns an integer less than, equal to, or greater than zero,
depending on if $x is less than, equal to, or greater than $y.
Introduced in PHP 7.
PH P IN CR E ME N T / D E CRE M EN T O PE R ATOR S
The PHP increment operators are used to increment a variable's value.
The PHP decrement operators are used to decrement a variable's value
Operator Same as... Description
++$x Pre-increment Increments $x by one, then returns $x
$x++ Post-increment Returns $x, then increments $x by one
--$x Pre-decrement Decrements $x by one, then returns $x
$x-- Post-decrement Returns $x, then decrements $x by one
P H P L O G I C A L O P E R AT O R S
The PHP logical operators are used to combine conditional statements.
Operator Name Example Result
and And $x and $y True if both $x and $y are true
or Or $x or $y True if either $x or $y is true
xor Xor $x xor $y True if either $x or $y is true, but not
both
&& And $x && $y True if both $x and $y are true
|| Or $x || $y True if either $x or $y is true
! Not !$x True if $x is not true
P H P S T R I N G O P E R AT O R S
PHP has two operators that are specially designed for strings.
Operator Name Example Result
. Concatenation $txt1 . $txt2 Concatenation of $txt1 and $txt2
.= Concatenation
assignment
$txt1 .= $txt2 Appends $txt2 to $txt1
P H P A R R AY O P E R ATO R S
The PHP array operators are used to compare arrays.
Operator Name Example Result
+ Union $x + $y Union of $x and $y
== Equality $x == $y Returns true if $x and $y have the same
key/value pairs
=== Identity $x === $y Returns true if $x and $y have the same
key/value pairs in the same order and of the
same types
!= Inequality $x != $y Returns true if $x is not equal to $y
<> Inequality $x <> $y Returns true if $x is not equal to $y
!== Non-identity $x !== $y Returns true if $x is not identical to $y
P H P C O N D I T I O N A L A S S I G N M E N T O P E R ATO R S
The PHP conditional assignment operators are used to set a value depending on
conditions:
Operator Name Example Result
?: Ternary $x
= expr1 ? expr2 : e
xpr3
Returns the value of $x.
The value of $x is expr2 if expr1 =
TRUE.
The value of $x is expr3 if expr1 =
FALSE
?? Null coalescing $x = expr1 ?? expr2 Returns the value of $x.
The value of $x
is expr1 if expr1 exists, and is not
NULL.
If expr1 does not exist, or is NULL,
the value of $x is expr2.
PHP IF STATEMENTS
if statement - executes some code if one condition is true.
<?php
if (5 > 3) {
echo "Have a good day!";
}
?>
Output - Have a good day!
P H P I F. . . E L S E S TAT E M E N T S
The if...else statement executes some code if a condition is true and another code if that condition is
false.
<?php
$t = date("H");
if ($t < "20") {
echo "Have a good day!";
} else {
echo "Have a good night!";
}
?>
Output - Have a good day!
I F. . . E LS E I F. . . E LS E S TAT E ME NT
The if...elseif...else statement executes different codes for more than two conditions.
<?php
if ($t < "10") {
echo "Have a good morning!";
} elseif ($t < "20") {
echo "Have a good day!";
} else {
echo "Have a good night!";
}
?>
Output - Have a good day!
THANK
YOU

PHP PPT.pptxPHP PPT.pptxPHP PPT.pptxPHP n

  • 1.
    PHP (BASICS) • PHPDefination • PHP Syntax • PHP Comments • PHPVariables • ECHO and PRINT • PHP Datatypes • PHP Constents • PHP Operators
  • 2.
    P H P •PHP is a server scripting language, and a powerful tool for making dynamic and interactive Web pages. What is PHP? • PHP is an acronym for "PHP: Hypertext Preprocessor" • PHP is a widely-used, open source scripting language • PHP scripts are executed on the server • PHP is free to download and use What is a PHP File? • PHP files have extension ".php"
  • 3.
    WHAT CAN PHPDO? • PHP can generate dynamic page content • PHP can create, open, read, write, delete, and close files on the server • PHP can collect form data • PHP can send and receive cookies • PHP can add, delete, modify data in your database • PHP can be used to control user-access • PHP can encrypt data
  • 4.
    P H PS Y N T A X P H P C O M M E N T S <html> <body> <h1>My first PHP page</h1> <?php echo "Hello World!"; ?> </body> </html> // Outputs a welcome message: echo "Welcome Home!"; Multi-line Comments Multi-line comments start with /* and end with */. Any text between /* and */ will be ignored.
  • 5.
    PHP VARIABLES • Avariable 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 • Variable names are case-sensitive Example- $x = 5; $y = "John"
  • 6.
    P H PVA R I A B L E S S C O P E The scope of a variable is the part of the script where the variable can be referenced/used. PHP has three different variable scopes: • local • global • static
  • 7.
    GLOBAL AND LOCALSCOPE • A variable declared outside a function has a GLOBAL SCOPE and can only be accessed outside a function. Global Scope <?php $x = 5; // global scope function myTest() { // using x inside this function will generate an error echo "<p>Variable x inside function is: $x</p>"; } myTest(); echo "<p>Variable x outside function is: $x</p>"; ?> Output - Variable x inside function is: Variable x outside function is: 5
  • 8.
    LOCAL SCOPE <?php function myTest(){ $x = 5; // local scope echo "<p>Variable x inside function is: $x</p>"; } myTest(); // using x outside the function will generate an error echo "<p>Variable x outside function is: $x</p>"; ?> Output - Variable x inside function is: 5 Variable x outside function is:
  • 9.
    P H PE C H O A N D P R I N T S T A T E M E N T S echo and print are more or less the same.They are both used to output data to the screen. • The differences are small: echo has no return value while print has a return value of 1 so it can be used in expressions. • echo can take multiple parameters (although such usage is rare) while print can take one argument. echo is marginally faster than print.
  • 10.
    P H PD A T A T Y P E S Variables can store data of different types, and different data types can do different things. PHP supports the following data types: • String • Integer • Float (floating point numbers - also called double) • Boolean • Array • NULL
  • 11.
    P H PS T R I N G A string is a sequence of characters, like "Hello world!“. <?php $x = "Hello world!"; $y = 'Hello world!'; var_dump($x); echo "<br>"; var_dump($y); ?> Output - string(12) "Hello world!" string(12) "Hello world!"
  • 12.
    P H PI N T E G E R • An integer must have at least one digit • An integer must not have a decimal point • An integer can be either positive or negative • Integers can be specified in: decimal (base 10), hexadecimal (base 16), octal (base 8), or binary (base 2) notation <?php $x = 5985; var_dump($x); ?> Output - int(5985)
  • 13.
    PHP FLOAT • Afloat (floating point number) is a number with a decimal point or a number in exponential form. • In the following example $x is a float.The PHP var_dump() function returns the data type and value: <?php $x = 10.365; var_dump($x); ?> Output - float(10.365)
  • 14.
    PHP BOOLEAN A Booleanrepresents two possible states:TRUE or FALSE. <html> <body> <?php $x = true; var_dump($x); ?> </body> </html> Output - bool(true)
  • 15.
    P H PA R R A Y • An array stores multiple values in one single variable. • In the following example $cars is an array.The PHP var_dump() function returns the data type and value: <?php $cars = array("BMW","Toyota"); var_dump($cars); ?> Output – array(2) { [0]=> string(3) "BMW" [1]=> string(6) "Toyota" }
  • 16.
    P H PC A S T I N G Change DataType Casting in PHP is done with these statements: (string) - Converts to data type String (int) - Converts to data type Integer (float) - Converts to data type Float (bool) - Converts to data type Boolean (array) - Converts to data type Array (object) - Converts to data type Object (unset) - Converts to data type NULL
  • 17.
    <?php $a="first step"; $b="2"; $c="true"; $d="3.89"; $f="null"; $a= (string)$a; $b= (array) $b; $c= (bool) $c; $d= (float) $d; $f= (string) $f; //To verify the type of any object in PHP, use the var_dump() funtion: var_du($a); echo"<br>"; var_dump($b); echo"<br>"; var_dump($c); echo"<br>"; var_dump($d); echo"<br>"; var_dump($f); ?> OUTPUT : string(10) "first step" array(1) { [0]=> string(1) "2" } bool(true) float(3.89) string(4) "null"
  • 18.
    P H PC O N S T A N T S • Constants are like variables, except that once they are defined they cannot be changed or undefined. • A constant is an identifier (name) for a simple value. The value cannot be changed during the script. • A valid constant name starts with a letter or underscore (no $ sign before the constant name) Syntax: define(name, value, case-insensitive);
  • 19.
    P H PO P E R ATO R S Operators are used to perform operations on variables and values. PHP divides the operators in the following groups: • Arithmetic operators • Assignment operators • Comparison operators • Increment/Decrement operators • Logical operators • String operators • Array operators • Conditional assignment operators
  • 20.
    PHP ARITHMETIC OPERATORS ThePHP arithmetic operators are used with numeric values to perform common arithmetical operations, such as addition, subtraction, multiplication etc. Operator Name Example Result + Addition $x + $y Sum of $x and $y - Subtraction $x - $y Difference of $x and $y * Multiplication $x * $y Product of $x and $y / Division $x / $y Quotient of $x and $y % Modulus $x % $y Remainder of $x divided by $y ** Exponentiation $x ** $y Result of raising $x to the $y'th power
  • 21.
    P H PA S S I G N M E N T O P E R AT O R S The PHP assignment operators are used with numeric values to write a value to a variable Assignment Same as... Description x = y x = y The left operand gets set to the value of the expression on the right x += y x = x + y Addition x -= y x = x - y Subtraction x *= y x = x * y Multiplication x /= y x = x / y Division x %= y x = x % y Modulus
  • 22.
    P H PC O M PA R I S O N O P E R ATO R S The PHP comparison operators are used to compare two values (number or string): Operator Name Example Result == Equal $x == $y Returns true if $x is equal to $y === Identical $x === $y Returns true if $x is equal to $y, and they are of the same type != Not equal $x != $y Returns true if $x is not equal to $y <> Not equal $x <> $y Returns true if $x is not equal to $y !== Not identical $x !== $y Returns true if $x is not equal to $y, or they are not of the same type > Greater than $x > $y Returns true if $x is greater than $y < Less than $x < $y Returns true if $x is less than $y >= Greater than or equal to $x >= $y Returns true if $x is greater than or equal to $y <= Less than or equal to $x <= $y Returns true if $x is less than or equal to $y <=> Spaceship $x <=> $y Returns an integer less than, equal to, or greater than zero, depending on if $x is less than, equal to, or greater than $y. Introduced in PHP 7.
  • 23.
    PH P INCR E ME N T / D E CRE M EN T O PE R ATOR S The PHP increment operators are used to increment a variable's value. The PHP decrement operators are used to decrement a variable's value Operator Same as... Description ++$x Pre-increment Increments $x by one, then returns $x $x++ Post-increment Returns $x, then increments $x by one --$x Pre-decrement Decrements $x by one, then returns $x $x-- Post-decrement Returns $x, then decrements $x by one
  • 24.
    P H PL O G I C A L O P E R AT O R S The PHP logical operators are used to combine conditional statements. Operator Name Example Result and And $x and $y True if both $x and $y are true or Or $x or $y True if either $x or $y is true xor Xor $x xor $y True if either $x or $y is true, but not both && And $x && $y True if both $x and $y are true || Or $x || $y True if either $x or $y is true ! Not !$x True if $x is not true
  • 25.
    P H PS T R I N G O P E R AT O R S PHP has two operators that are specially designed for strings. Operator Name Example Result . Concatenation $txt1 . $txt2 Concatenation of $txt1 and $txt2 .= Concatenation assignment $txt1 .= $txt2 Appends $txt2 to $txt1
  • 26.
    P H PA R R AY O P E R ATO R S The PHP array operators are used to compare arrays. Operator Name Example Result + Union $x + $y Union of $x and $y == Equality $x == $y Returns true if $x and $y have the same key/value pairs === Identity $x === $y Returns true if $x and $y have the same key/value pairs in the same order and of the same types != Inequality $x != $y Returns true if $x is not equal to $y <> Inequality $x <> $y Returns true if $x is not equal to $y !== Non-identity $x !== $y Returns true if $x is not identical to $y
  • 27.
    P H PC O N D I T I O N A L A S S I G N M E N T O P E R ATO R S The PHP conditional assignment operators are used to set a value depending on conditions: Operator Name Example Result ?: Ternary $x = expr1 ? expr2 : e xpr3 Returns the value of $x. The value of $x is expr2 if expr1 = TRUE. The value of $x is expr3 if expr1 = FALSE ?? Null coalescing $x = expr1 ?? expr2 Returns the value of $x. The value of $x is expr1 if expr1 exists, and is not NULL. If expr1 does not exist, or is NULL, the value of $x is expr2.
  • 28.
    PHP IF STATEMENTS ifstatement - executes some code if one condition is true. <?php if (5 > 3) { echo "Have a good day!"; } ?> Output - Have a good day!
  • 29.
    P H PI F. . . E L S E S TAT E M E N T S The if...else statement executes some code if a condition is true and another code if that condition is false. <?php $t = date("H"); if ($t < "20") { echo "Have a good day!"; } else { echo "Have a good night!"; } ?> Output - Have a good day!
  • 30.
    I F. .. E LS E I F. . . E LS E S TAT E ME NT The if...elseif...else statement executes different codes for more than two conditions. <?php if ($t < "10") { echo "Have a good morning!"; } elseif ($t < "20") { echo "Have a good day!"; } else { echo "Have a good night!"; } ?> Output - Have a good day!
  • 31.