PHP Manual: Shuffle an array

Description

bool shuffle ( array &$array )

This function shuffles (randomizes the order of the elements in) an array. It uses a pseudo random number generator that is not suitable for cryptographic purposes.

Note:
If two members compare as equal, their relative order in the sorted array is undefined.

Parameters

array: The array.

Return Values

Returns TRUE on success or FALSE on failure.

Changelog

Version	Description
7.1.0	The internal randomization algorithm has been changed to use the » Mersenne Twister Random Number Generator instead of the libc rand function.

Examples

Example #1 shuffle example


<?php
$numbers = range(1, 20);
shuffle($numbers);
foreach ($numbers as $number) {
    echo "$number ";
}
?>

Notes

Note: This function assigns new keys to the elements in array. It will remove any existing keys that may have been assigned, rather than just reordering the keys.

shuffle