uksort

uksort -- Sort an array by keys using a user-defined comparison function

Description

void uksort(array array, function cmp_function);

This function will sort the keys of an array using a user-supplied comparison function. If the array you wish to sort needs to be sorted by some non-trivial criteria, you should use this function.

Example 1. uksort() example

function mycompare($a, $b) {   
    if ($a == $b) return 0;
    return ($a > $b) ? -1 : 1;
}
$a = array(4 => "four", 3 => "three", 20 => "twenty", 10 => "ten");
uksort($a, mycompare);
while(list($key, $value) = each($a)) {
    echo "$key: $value\n";
}
This example would display: 20: twenty 10: ten 4: four 3: three

See also: arsort(), asort(), uasort(), ksort(), rsort(), and sort().