PHP Operators

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

PHP Operators with Example

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 (Introduced in PHP 5.6)
<?php 
$x = 8; 
$y = 2;
 
echo $x + $y."\n";
echo $x - $y."\n";
echo $x * $y."\n";
echo $x / $y."\n";
echo $x % $y."\n";
echo $x ** $y."\n";
?>   

Run : http://ideone.com/EwZM3b

Tutorials Class - Output Window

10
6
16
4
0
64


Assignment operators

The PHP assignment operators are used with numeric values to write 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.

  • 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
<?php 
$x = 10; 
$y = 20;

$res=$x = $y;
echo $res."<br>";
 
$res= $x += $y;
echo $res."<br>";

$res= $x -= $y;
echo $res."<br>";
 
$res= $x *= $y;
echo $res."<br>";

$res= $x /= $y;
echo $res."<br>";

$res= $x %= $y;
echo $res."<br>";
?>

Run : http://ideone.com/U8sJHv

Tutorials Class - Output Window

20
40
20
400
20
0


Comparison Operators

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

Increment / Decrement Operators

The PHP 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

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

String Operators

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

Array Operators

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

PHP Operators – Assignment & Exercises
Write a program to add two numbers ’10’ and ‘5’
Write a program to subtract number ‘3’ from ’12’
Write a program to subtract number ’10’ from ‘5’
Write a program to multiply two numbers ‘7’ and ’11’
Write a program to divide ’10’ by ‘4’ (10/4) and check the output.
Write a program to check the remainder (using Modulus), when ’10’ divided by ‘4’.

Congratulations! Chapter Finished. Learn more about the similar topics:
Exercises & Assignments
Write a PHP program to check whether a number is positive, negative or zero
Interview Questions & Answers
What is the difference between == and === Operators in PHP?