array_udiff_assoc
(PHP 5, PHP 7, PHP 8)
Computes the difference of arrays with additional index check, compares data by a callback function
Description
Computes the difference of arrays with additional index check, compares data by a callback function.
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_assoc($array1[0], $array2[0], "some_comparison_func");.
Parameters
arrayThe first array.
arraysArrays to compare against.
value_compare_funcDescription Presort
Return Values
array_udiff_assoc() returns an array containing all the values from array that are not present in any of the other arguments. Note that the keys are used in the comparison unlike array_diff() and array_udiff(). The comparison of arrays' data is performed by using an user-supplied callback. In this aspect the behaviour is opposite to the behaviour of array_diff_assoc() which uses internal function for comparison.
Examples
array_udiff_assoc() example
<?php
class cr {
private $priv_member;
function __construct($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;
}
}
$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),);
$result = array_udiff_assoc($a, $b, array("cr", "comp_func_cr"));
print_r($result);
?>The above example will output:
Array
(
[0.1] => cr Object
(
[priv_member:cr:private] => 9
)
[0.5] => cr Object
(
[priv_member:cr:private] => 12
)
[0] => cr Object
(
[priv_member:cr:private] => 23
)
)In our example above you see the "1" => new cr(4) pair is present in both arrays and thus it is not in the output from the function.