array_diff_uassoc

Syntax:array array_diff_uassoc ( array $array1 , array $array2 [, array $... ], callable $key_compare_func ) Description:Computes the difference of arrays with additional index check which is performed by a user supplied callback function

<?php
function key_compare_func($a, $b)
{
    if ($a === $b) {
        return 0;
    }
    return ($a > $b)? 1:-1;
}
$array1 = array("a" => "green", "b" => "brown", "c" => "blue", "red");
$array2 = array("a" => "Green", "yellow", "D"=>"Blue");
$result = array_diff_uassoc($array1, $array2, "key_compare_func");
print_r($result);
?>

OUTPUT

Array ( 
[a] => green 
[b] => brown 
[\c] => blue 
[0] => red 
)