array_uintersect_assoc Computes the intersection of arrays with additional index check, compares data by a callback function arrayarray_uintersect_assoc arrayarray1 arrayarray2 array ... callbackdata_compare_func array_uintersect_assoc returns an array containing all the values of array1 that are present in all the arguments. Note that the keys are used in the comparison unlike in array_uintersect. The data is compared by using a callback function. "green", "b" => "brown", "c" => "blue", "red"); $array2 = array("a" => "GREEN", "B" => "brown", "yellow", "red"); print_r(array_uintersect_assoc($array1, $array2, "strcasecmp")); ?> ]]> &example.outputs; green ) ]]> 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. See also array_uintersect, array_intersect_assoc, array_intersect_uassoc and array_uintersect_uassoc.