1 common.inc backdrop_array_diff_assoc_recursive($array1, $array2)

Recursively computes the difference of arrays with additional index check.

This is a version of array_diff_assoc() that supports multidimensional arrays.


array $array1: The array to compare from.

array $array2: The array to compare to.

Return value

array: Returns an array containing all the values from array1 that are not present in array2.


core/includes/common.inc, line 7526
Common functions that many Backdrop modules will need to reference.


function backdrop_array_diff_assoc_recursive($array1, $array2) {
  $difference = array();

  foreach ($array1 as $key => $value) {
    if (is_array($value)) {
      if (!array_key_exists($key, $array2) || !is_array($array2[$key])) {
        $difference[$key] = $value;
      else {
        $new_diff = backdrop_array_diff_assoc_recursive($value, $array2[$key]);
        if (!empty($new_diff)) {
          $difference[$key] = $new_diff;
    elseif (!array_key_exists($key, $array2) || $array2[$key] !== $value) {
      $difference[$key] = $value;

  return $difference;