(PHP 5)
array_uintersect_assoc — Computes the intersection of arrays with additional index check, compares data by a callback function
$array1
   , array $array2
   [, array $...
   ], callable $value_compare_func
   )Computes the intersection of arrays with additional index check, compares data by a callback function.
Note that the keys are used in the comparison unlike in array_uintersect(). The data is compared by using a callback function.
array1
     The first array.
array2
     The second array.
value_compare_func
     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.
   Returns an array containing all the values of
   array1 that are present in all the arguments.
  
Example #1 array_uintersect_assoc() example
<?php
$array1 = array("a" => "green", "b" => "brown", "c" => "blue", "red");
$array2 = array("a" => "GREEN", "B" => "brown", "yellow", "red");
print_r(array_uintersect_assoc($array1, $array2, "strcasecmp"));
?>
The above example will output:
Array
(
    [a] => green
)