array_uintersect Computes the intersection of arrays, compares data by a callback function arrayarray_uintersect arrayarray1 arrayarray2 array ... callbackdata_compare_func array_uintersect returns an array containing all the values of array1 that are present in all the arguments. The data is compared by using a callback function. "green", "b" => "brown", "c" => "blue", "red"); $array2 = array("a" => "GREEN", "B" => "brown", "yellow", "red"); print_r(array_uintersect($array1, $array2, "strcasecmp")); ?> ]]> &example.outputs; green [b] => brown [0] => red ) ]]> 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_intersect, array_uintersect_assoc, array_intersect_uassoc and array_uintersect_uassoc.