PHP usort()Functions

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Examples

Sort the elements in array $a using a user-defined comparison function: Sort the elements of the $a array using a user-defined comparison function:

<?php
function my_sort($a,$b)
{
if ($a==$b) return 0;
return ($a<$b)?-1:1;
}

$a=array(4,2,8,6);
usort($a,"my_sort");
?>

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Definition and Usage

usort() sorts an array using a user-defined comparison function.

Syntax

usort(array,myfunction);

Parameters Description
array Required. Specifies the array to sort.
myfunction Optional. A string that defines a callable comparison function. If the first argument is <, =, > the second argument, the comparison function must return an integer that is <, =, > 0 respectively.

Technical Details

Return value: Returns TRUE on success, or FALSE on failure.
PHP version: 4+


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