PHP shuffle() Function
Topic: PHP Array ReferencePrev|Next
Description
The shuffle()
function shuffles an array (i.e. randomizes the order of the array elements).
The following table summarizes the technical details of this function.
Return Value: | Returns TRUE on success or FALSE on failure. |
---|---|
Changelog: | Since PHP 7.1.0, the internal randomization algorithm has been changed to use the Mersenne Twister random number generator instead of the libc rand function. |
Version: | PHP 4+ |
Syntax
The basic syntax of the shuffle()
function is given with:
The following example shows the shuffle()
function in action.
Example
Run this code »<?php
// Sample array
$colors = array("red", "green", "blue", "orange", "yellow", "black");
// Shuffling the indexed array colors
shuffle($colors);
print_r($colors);
?>
Note: The shuffle()
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.
Parameters
The shuffle()
function accepts the following parameters.
Parameter | Description |
---|---|
array | Required. Specifies the array to work on. |
More Examples
Here're some more examples showing how shuffle()
function actually works:
You can also shuffle an associative array, but the original keys will be removed, as stated above.
Example
Run this code »<?php
// Sample array
$alphabets = array("a"=>"apple", "b"=>"ball", "c"=>"cat", "d"=>"dog");
// Sorting the associative array alphabets
shuffle($alphabets);
print_r($alphabets);
?>