PHP » Operators » &=

Syntax:
$var &= expression
var
A variable.
expression
Value to AND the variable with.

Bitwise AND assignment operator.

The variable is assigned the value of var & expression.

Examples

Code:
<?php

$a = 11;
$a &= 15;
printf("%b", $a);

?>
Output:
1011
Explanation:

A variable is changed with an assignment operator.