array_udiff_uassoc

(PHP 5, PHP 7)

Computes the difference of arrays with additional index check, compares data and indexes by a callback function

array array_udiff_uassoc ( array $array1, array $array2 [, array $... ], callable $value_compare_func, callable $key_compare_func )

Computes the difference of arrays with additional index check, compares data and indexes by a callback function.

Note that the keys are used in the comparison unlike array_diff() and array_udiff().

Parameters:

array1

The first array.

array2

The second array.

value_compare_func

The comparison function must return an integer less than, equal to, or greater than zero if the first argument is considered to be respectively less than, equal to, or greater than the second.

int callback ( mixed $a, mixed $b )

key_compare_func

The comparison of keys (indices) is done also by the callback function key_compare_func. This behaviour is unlike what array_udiff_assoc() does, since the latter compares the indices by using an internal function.

Returns:

Returns an array containing all the values from array1 that are not present in any of the other arguments.

Notes:

Please note that this function only checks one dimension of a n-dimensional array. Of course you can check deeper dimensions by using, for example, array_udiff_uassoc($array1[0], $array2[0], "data_compare_func", "key_compare_func");.

Examples:

array_udiff_uassoc() example

<?php
class cr {
    private $priv_member;
    function cr($val)
    {
        $this->priv_member = $val;
    }

    static function comp_func_cr($a, $b)
    {
        if ($a->priv_member === $b->priv_member) return 0;
        return ($a->priv_member > $b->priv_member)? 1:-1;
    }

    static function comp_func_key($a, $b)
    {
        if ($a === $b) return 0;
        return ($a > $b)? 1:-1;
    }
}
$a = array("0.1" => new cr(9), "0.5" => new cr(12), 0 => new cr(23), 1=> new cr(4), 2 => new cr(-15),);
$b = array("0.2" => new cr(9), "0.5" => new cr(22), 0 => new cr(3), 1=> new cr(4), 2 => new cr(-15),);

$result = array_udiff_uassoc($a, $b, array("cr", "comp_func_cr"), array("cr", "comp_func_key"));
print_r($result);
?>

The above example will output:

Array
(
    [0.1] => cr Object
        (
            [priv_member:private] => 9
        )

    [0.5] => cr Object
        (
            [priv_member:private] => 12
        )

    [0] => cr Object
        (
            [priv_member:private] => 23
        )
)