Operators in PHP with types and examples

Operators are special symbols or keywords in PHP that carry out specific operations on variables or values. Arithmetic, comparison, logical, assignment, and bitwise operators are all supported by PHP.

Types of operators in PHP

• Arithmetic operators
• Comparison operators
• Logical operators
• Assignment operators
• Bitwise operators
• Increment/Decrement operators
• Conditional operators

These are the main operators in PHP. Let's explain these operators one by one.

Arithmetic operators in PHP

Arithmetic operators carry out mathematical operations on numbers. The following arithmetic operators are supported by PHP:

PHP arithmetic operator example

<?php 
   $a = 11;
   $b = 5;
   
   echo $a + $b;
   echo "<BR>";
   
   echo $a - $b;
   echo "<BR>";
   
   echo $a * $b;
   echo "<BR>";
   
   echo $a / $b;
   echo "<BR>";
   
   echo $a % $b;
?>

16
6
55
2.2
1

Comparison operators in PHP

The comparison operator compares two values and returns a Boolean result. The following comparison operators are supported by PHP:

PHP comparison operators example

<?php 
   $a = 11;
   $b = 5;
   $c = 11;
   
   echo $a == $c;
   echo "<BR>";
   
   echo $a != $b;
   echo "<BR>";
   
   echo $a === $c;
   echo "<BR>";
   
   echo $a !== $b;
   echo "<BR>";
   
   echo $a > $b;
   echo "<BR>";
   
   echo $b < $c;
   echo "<BR>";
   
   echo $a >= $b;
   echo "<BR>";
   
   echo $b <= $c;
?>

1
1
1
1
1
1
1
1

Logical operators in PHP

A Boolean result is produced by combining two or more Boolean expressions using logical operators. The following logical operators are supported by PHP:

PHP logical operators example

<?php 
   $a = true;
   $b = false;
   $c = true;
   
   echo $a && $c;
   echo "<BR>";
   
   echo $a || $c;
   echo "<BR>";
   
   echo !$b;
?>

1
1
1

Assignment operators in PHP

Variables can have values assigned to them using assignment operators. The following assignment operators are supported by PHP:

PHP assignment operators example

<?php 
   $a = 11;
   $b = 5;
   
   $a += $b;
   echo $a;
   echo "<BR>";
   
   $a -= $b;
   echo $a;
   echo "<BR>";
   
   $a *= $b;
   echo $a;
   echo "<BR>";
   
   $a /= $b;
   echo $a;
   echo "<BR>";
   
   $a %= $b;
   echo $a;
?>

16
11
55
11
1

The following statement:

$a += $b;

is equivalent to

$a = $a + $b;

Similarly, the following statement:

$a -= $b;

is equivalent to

$a = $a - $b;

and so on.

Bitwise operators in PHP

Bitwise operators operate on numeric values' binary representations. PHP supports the bitwise operators listed below:

PHP bitwise operators example

<?php 
   $a = 10;
   $b = 5;
   
   echo $a & $b;
   echo "<BR>";
   
   echo $a | $b;
   echo "<BR>";
   
   echo $a ^ $b;
   echo "<BR>";
   
   echo ˜$a;
   echo "<BR>";
   
   echo $a << 1;
   echo "<BR>";
   
   echo $a >> 1;
?>

0
15
15
-11
20
5

The binary equivalent of 10 is 1010, 5 is 0101, 0 is 0000, 15 is 1111, -11 is 11110101, and 20 is 10100.

Increment/Decrement operators in PHP

The increment/decrement operators in PHP are used to change a variable's value by one. Since they only operate on one variable, they are categorized as unary operators.

A variable's value is increased by the increment operator (++) by 1 and decreased by the decrement operator (--) by 1. The order in which these operators are used can have an impact on the operation's outcome. These operators can be used either before or after the variable they are operating on.

This type of increment/decrement operator is known as a pre-increment/pre-decrement operator because it is applied before the variable. The variable's value is altered before it is plugged into the expression. Post-increment or post-decrement operators are those that come after the variable they are modifying. Here, the variable's value is changed after it has been used in an expression.

PHP Increment/Decrement operators example

<?php 
   $a = 5;
   echo ++$a;     // increments, then use
   echo "<BR>";
   
   echo $a;
   echo "<BR>";
   
   echo $a++;     // use, then increments
   echo "<BR>";
   
   echo $a;
   echo "<BR>";

   $b = 5;
   echo --$b;     // decrements, then use
   echo "<BR>";
   
   echo $b;
   echo "<BR>";
   
   echo $b--;     //  use, then decrements
   echo "<BR>";
   
   echo $b;
?>

6
6
6
7
4
4
4
3

Conditional operators in PHP

The conditional operator in PHP is a one-line shortcut for writing an if-else statement. The syntax is as follows:

condition ? x : y;

The "condition" will be evaluated first; if it is evaluated as true, then "x" will be returned, otherwise "y" will be returned.

PHP conditional operator example

<?php 
   $a = 5;
   $b = 10;
   
   $c = $a>$b ? "codes" : "cracker";
   echo $c;
   echo "<BR>";
   
   $d = $a<$b ? "codes" : "cracker";
   echo $d;
?>

cracker
codes

The step-by-step explanation of the previous code is:

• $a is assigned the value 5
• $b is assigned the value 10
• $c is assigned the value "codes" if $a is greater than $b, and "cracker" otherwise. This is done using the ternary operator ? :
• $d is assigned the value "codes" if $a is less than $b, and "cracker" otherwise. Again, this is done using the ternary operator

The code then prints out the values of $c and $d separated by a line break (<BR>).

Since $a is not greater than $b, $c is assigned the value "cracker". And, since $a is less than $b, so $d is assigned the value "codes".

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