(PHP 5)array_udiff_assoc -- Computes the difference of arrays with additional index check. The data is compared by using a callback function.
array_udiff_assoc() returns an array containing all the values from array1 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.
Esempio 1. array_udiff_assoc() example
The result is:
In our example above you see the "1" => new cr(4) pair is present in both arrays and thus it is not in the ouput from the function.
For comparison is used the user supplied callback function. It 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.
Nota: 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, $array2, "some_comparison_func");.
See also array_diff(), array_diff_assoc(), array_diff_uassoc(), array_udiff(), array_udiff_uassoc(), array_intersect(), array_intersect_assoc(), array_uintersect(), array_uintersect_assoc() and array_uintersect_uassoc().