Definition
The array_diff_ukey() function compares the keys of two (or more) arrays, and return an array that contains the entries from array1 that are not present in array2 or array3, etc, using a user-defined function to compare the keys.
Syntax
array_diff_ukey(array1, array2, array3, ..., myfunction)
Parameters
| Parameter | Description |
|---|---|
array1 |
Required. The array to compare from. |
array2 |
Required. An array to compare against. |
array3 |
Optional. More arrays to compare against. |
myfunction |
Required. A string that define a callable comparison function. The comparison function must return an integer <, =, or > than 0 if the first argument is <, =, or > than the second argument. |
Example
<?php
function compare($x, $y){
$x = strtolower($x);
$y = strtolower($y);
if($x == $y){
return 0;
}
return ($x < $y) ? -1 : 1;
}
$array1 = array("cat" => 2, "lion" => 5, "zebra" => 8);
$array2 = array("CAT" => 3, "FOX" => 1, "LION" => 5, "WOLF" => 7);
$result = array_diff_ukey($array1, $array2, "compare");
print_r($result);