Operators are used to perform operations on variables and values.
PHP has many operators which are divided into following categories:
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 |
+ |
Addition |
2+4 |
- |
Substraction |
6-2 |
* |
Multiplication |
5 * 3 |
/ |
Division |
15 / 3 |
% |
Modulus |
43 % 10 |
Example
<?php
$addition = 2 + 4;
$subtraction = 6 - 2;
$multiplication = 5 * 3;
$division = 15 / 3;
$modulus = 5 % 2;
echo "Perform addition: 2 + 4 = ".$addition."<br />";
echo "Perform subtraction: 6 - 2 = ".$subtraction."<br />";
echo "Perform multiplication: 5 * 3 = ".$multiplication."<br />";
echo "Perform division: 15 / 3 = ".$division."<br />";
echo "Perform modulus: 5 % 2 = " . $modulus. ". Modulus is the remainder after the division operation has been performed.
In this case it was 5 / 2, which has a remainder of 1.";
?>
Output:
Perform addition: 2 + 4 = 6
Perform subtraction: 6 - 2 = 4
Perform multiplication: 5 * 3 = 15
Perform division: 15 / 3 = 5
Perform modulus: 5 % 2 = 1. Modulus is the remainder after the division operation has been performed. In this case it was 5 / 2, which has a remainder of 1.
Assignment Operators
The PHP assignment operators are used with numeric values to assign a value to a variable.
The basic assignment operator in PHP is "=". It means that the left operand gets set to the value of the assignment expression on the right.
Operator |
Name |
Example |
Equivalent Operation |
+= |
Plus Equals |
$x += 2; |
$x = $x + 2; |
-= |
Minus Equals |
$x -= 4; |
$x = $x - 4; |
*= |
Multiply Equals |
$x *= 3; |
$x = $x * 3; |
/= |
Divide Equals |
$x /= 2; |
$x = $x / 2; |
%= |
Modulo Equals |
$x %= 5; |
$x = $x % 5; |
.= |
Concatenate Equals |
$my_str.="hello"; |
$my_str = $my_str . "hello"; |
PHP Comparison Operators
Comparisons are used to check the relationship between variables/values. Comparison operators are used inside conditional statements and evaluate to either true or false. Here are the most important comparison operators of PHP.
Operator |
Name |
Example |
== |
Equal |
$x == $y |
=== |
Identical |
$x === $y |
!= |
Not equal |
$x != $y |
<> |
Not equal |
$x <> $y |
!== |
Not identical |
$x !== $y |
> |
Greater than |
$x > $y |
< |
Less than |
$x < $y |
>= |
Greater than or equal to |
$x >= $y |
<= |
Less than or equal to |
$x <= $y |
Increment / Decrement Operators
The PHP increment operators are used to increment a variable's value and the decrement operators are used to decrement a variable's value.
Operator |
Name |
Description |
++$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 |
Logical Operators
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 |
String Operators
There are two operators that are specially designed for strings.
Operator |
Name |
Example |
. |
Concatenation |
$txt1 . $txt2 |
.= |
Concatenation assignment |
$txt1 .= $txt2 |
Array Operators
The PHP array operators are used to compare arrays.
Operator |
Name |
Example |
+ |
Union |
$x + $y |
== |
Equality |
$x == $y |
=== |
Identity |
$x === $y |
!= |
Inequality |
$x != $y |
<> |
Inequality |
$x <> $y |
!== |
Non-identity |
$x !== $y |