Operators in php

Operators are used to perform operations on some values. Means using an expression 4 + 5 is equal to 9. Here 4 and 5 are operands and + is called operator. Given below are the various groups of operators:

• Arithmetic Operators
• Assignment Operators
• Comparison Operators
• Incrementing/Decrementing Operators
• Logical Operators
• String Operators
• Array Operators

1. Arithmetic Operators - The arithmetic operators are use to perform simple mathematical operations like addition, subtraction, multiplication etc.

Operator	Name	Syntax	Operation
+	Addition	$a + $b	Adds tow operands
-	Subtraction	$a - $b	Subtract second operand from the first
*	Multiplication	$a * $b	Multiply bot operands
/	Division	$a / $b	Divide numerator by de-numerator
%	Modulo	$a % $b	Reminder of the operands
**	Exponentiation	$a ** $b	$a raised to the power $y

Example 1 –

<?php

$a = 29; //Var 1

$b = 4; // var 2

echo ($a + $b), "\n"; // Output 33

echo($a - $b), "\n"; // Output 25

echo($a * $b), "\n"; // Output 116

echo($a / $b), "\n"; // Output 7.25

echo($a % $b), "\n"; // Output 1

?>

2. Assignment operator - The basic assignment operator is "=". These operators are used to assign values to different variable, with or without mid-operations.

Operator	Name	Syntax	Operation
=	Simple assignment operator	$a  =  $b	Assigns values from right side operands to left side operand
+=	Add and assignment operator	$a += $b	Adds right operand to the left operand and assign the result to left operand
-=	Subtract AND assignment operator	$a -= $b	Subtracts right operand from the left operand and assign the result to left operand
*=	Multiply AND assignment operator	$a *= $b	Multiplies right operand with the left operand and assign the result to left operand
/=	Divide AND assignment operator	$a /= $b	Divides left operand with the right operand and assign the result to left operand
%=	Modulus AND assignment operator	$a %= $b	Takes modulus using two operands and assign the result to left operand

<?php

// simple assign operator

$a = 75;

echo $a, "\n";

// add then assign operator

$a = 100;

$a += 200;

echo $a, "\n";

// subtract then assign operator

$a = 70;

$a -= 10;

echo $a, "\n";

// multiply then assign operator

$a = 30;

$a *= 20;

echo $a, "\n";

// Divide then assign(quotient) operator

$a = 100;

$a /= 5;

echo $y, "\n";

// Divide then assign(remainder) operator

$a = 50;

$a %= 5;

echo $a;

?>

3. Comparison operators - These operators are used to compare two elements and outputs the result in Boolean form.

Operator	Name	Syntax	Operation
==	Equal To	$a = =  $b	Checks if the value of two operands are equal then True otherwise False
!=	Not Equal To	$a != $b	If both the operands are equal then return True otherwise False
<>	Not Equal To	$a <> $b	If both the operands are unequal then return True otherwise False
===	Identical	$a === $b	If both operands are equal and the same type then return True otherwise False
!==	Not Identical	$a !== $b	If both operands are unequal and the different types then return True otherwise False
<	Less Than	$a < $b	If $a is less than $b then return True otherwise False
>	Greater Than	$a > $b	If $a is greater than $b then return True otherwise False
<=	Less Than or Equal To	$a <= $b	If $a is less than or equal to $b then return True otherwise False
>=	Greater Than or Equal To	$a >= $b	If $a is greater than or equal to $b then return True otherwise False

Example –

<?php

$x = 80;

$y = 50;

$z = "80";

/*Here used var_dump() function

explain in next tutorial */

var_dump($x == $z) + "\n";

var_dump($x != $y) + "\n";

var_dump($x <> $y) + "\n";

var_dump($x === $z) + "\n";

var_dump($x !== $z) + "\n";

var_dump($x < $y) + "\n";

var_dump($x > $y) + "\n";

var_dump($x <= $y) + "\n";

var_dump($x >= $y);

?>

4. Increment/Decrement operators - These are called the unary operators as it work on single operands. These are used to increment or decrement values. The PHP increment operators are used to increment a variable's value. And the decrement operators are used to decrement a variable's value.

Operator	Name	Syntax	Operation
++	Pre-Increment	++$a	Increments $a by one, then return $a
--	Pre-Decrement	--$a	Decrements $a by one, then return $a
++	Post-Increment	$a++	Return $a, then Increments $a by one
--	Post-Decrement	$a--	Return $a, then Decrements $a by one

Example –

<?php

$a = 2;

echo ++$a, " First increments then prints \n";

echo $a, "\n";

$a = 2;

echo $a++, " First prints then increments \n";

echo $a, "\n";

$a = 2;

echo --$a, " First decrements then prints \n";

echo $a, "\n";

$a = 2;

echo $a--, " First prints then decrements \n";

echo $a;

?>

5. Logical Operator - These are basically used to operate with conditional statements and expressions. Conditional statements are based on conditions. There are following logical operators supported by PHP language.

Operator	Name	Syntax	Operation
and	Logical AND	$a and $b	If both operands are true then True otherwise False
or	Logical OR	$a or $b	If either of the operands is true then True otherwise False
xor	Logical XOR	$a xor $b	If either of the operand is true then True and If both are true then False
&&	Logical AND	$a && $b	If both operands are true then True otherwise False
||	Logical OR	$a || $b	If either of the operands is true then True otherwise False
!	Logical NOT	!$a	If $a is false then True

Example –

<?php

$a = 50;

$b = 30;

if ($a == 50 and $b == 30)

            echo "and Success \n";

if ($a == 50 or $b == 20)

            echo "or Success \n";

if ($a == 50 xor $b == 20)

            echo "xor Success \n";

if ($a == 50 && $b == 30)

            echo "&& Success \n";

if ($a == 50 || $b == 20)

            echo "|| Success \n";

if (!$c)

            echo "! Success \n";

?>

6. String Operators - In PHP two operator specially design for string.

Operator	Name	Syntax	Operation
.	Concatenation	$text1.$text2	Concatenation of $text1 and $text2
.=	Concatenation and assignment	$text1.=$text2	First concatenates then assigns, same as $text1 = $text1.$text2

Example –

<?php

$a = "Hello";

$b = "Cyber";

$c = "Teak....";

echo $a . $b . $x, "\n";

$a .= $b . $c;

echo $a;

?>

7. Array operators - These operators are used in case of arrays.

Operator	Name	Syntax	Operation
+	Union	$a + $b	Union of $a + $b
==	Equality	$a == $b	If $a and $b have the same key / value pairs then return True
!=	Inequality	$a != $b	If $a is not equal to $b then return True
===	Identity	$a === $b	If $x and $y have the same key/value pairs in the same order and of the same types then return True
!==	Non-identity	$a !== $b	If $a is not identical to $y then return True
<>	Inequality	$a <> $b	If both are unequal then return True

Example –

<?php

$a = arrab("k" => "Car", "l" => "Bike");

$b = arrab("a" => "Train", "b" => "Plane");

var_dump($a + $b);

var_dump($a == $b) + "\n";

var_dump($a != $b) + "\n";

var_dump($a <> $b) + "\n";

var_dump($a === $b) + "\n";

var_dump($a !== $b) + "\n";

?>