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natsort

(PHP 4, PHP 5)

natsort — Sort an array using a "natural order" algorithm

Description

bool natsort ( array &$array )

This function implements a sort algorithm that orders alphanumeric strings in the way a human being would while maintaining key/value associations. This is described as a "natural ordering". An example of the difference between this algorithm and the regular computer string sorting algorithms (used in sort()) can be seen below:

Returns TRUE on success or FALSE on failure.

Example#1 natsort() example

<?php
$array1 
$array2 = array("img12.png""img10.png""img2.png""img1.png");

sort($array1);
echo 
"Standard sorting\n";
print_r($array1);

natsort($array2);
echo 
"\nNatural order sorting\n";
print_r($array2);
?>

The above example will output:

Standard sorting
Array
(
    [0] => img1.png
    [1] => img10.png
    [2] => img12.png
    [3] => img2.png
)

Natural order sorting
Array
(
    [3] => img1.png
    [2] => img2.png
    [1] => img10.png
    [0] => img12.png
)

For more information see: Martin Pool's » Natural Order String Comparison page.

See also natcasesort(), strnatcmp(), and strnatcasecmp().