array_udiff

(PHP 5)

array_udiffComputes the difference of arrays by using a callback function for data comparison

Description

array array_udiff ( array $array1 , array $array2 [, array $ ... ], callable $data_compare_func )

Computes the difference of arrays by using a callback function for data comparison. This is unlike array_diff() which uses an internal function for comparing the data.

Parameters

array1

The first array.

array2

The second array.

data_compare_func

The callback comparison function.

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 )

Return Values

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

Examples

Example #1 array_udiff() 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;
    }
}
$a = array("0.1" => new cr(9), "0.5" => new cr(12), => new cr(23), 1=> new cr(4), => new cr(-15),);
$b = array("0.2" => new cr(9), "0.5" => new cr(22), => new cr(3), 1=> new cr(4), => new cr(-15),);

$result array_udiff($a$b, array("cr""comp_func_cr"));
print_r($result);
?>

The above example will output:

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

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

)

Notes

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

See Also

  • array_diff() - Computes the difference of arrays
  • array_diff_assoc() - Computes the difference of arrays with additional index check
  • array_diff_uassoc() - Computes the difference of arrays with additional index check which is performed by a user supplied callback function
  • array_udiff_assoc() - Computes the difference of arrays with additional index check, compares data by a callback function
  • array_udiff_uassoc() - Computes the difference of arrays with additional index check, compares data and indexes by a callback function
  • array_intersect() - Computes the intersection of arrays
  • array_intersect_assoc() - Computes the intersection of arrays with additional index check
  • array_uintersect() - Computes the intersection of arrays, compares data by a callback function
  • array_uintersect_assoc() - Computes the intersection of arrays with additional index check, compares data by a callback function
  • array_uintersect_uassoc() - Computes the intersection of arrays with additional index check, compares data and indexes by a callback functions