function drupal_array_nested_key_exists in Drupal 7

Determines whether a nested array contains the requested keys.

This helper function should be used when the depth of the array element to be checked may vary (that is, the number of parent keys is variable). See drupal_array_set_nested_value() for details. It is primarily used for form structures and renderable arrays.

If it is required to also get the value of the checked nested key, use drupal_array_get_nested_value() instead.

If the number of array parent keys is static, this helper function is unnecessary and the following code can be used instead:

$value_exists = isset($form['signature_settings']['signature']);
$key_exists = array_key_exists('signature', $form['signature_settings']);

Parameters

$array: The array with the value to check for.

$parents: An array of parent keys of the value, starting with the outermost key.

Return value

TRUE if all the parent keys exist, FALSE otherwise.

See also

drupal_array_get_nested_value()

2 calls to drupal_array_nested_key_exists()

drupal_validate_form in includes/form.inc

Validates user-submitted form data in the $form_state array.

_form_builder_handle_input_element in includes/form.inc

Adds the #name and #value properties of an input element before rendering.

File

includes/common.inc, line 6983

Common functions that many Drupal modules will need to reference.

Code

function drupal_array_nested_key_exists(array $array, array $parents) {

  // Although this function is similar to PHP's array_key_exists(), its
  // arguments should be consistent with drupal_array_get_nested_value().
  $key_exists = NULL;
  drupal_array_get_nested_value($array, $parents, $key_exists);
  return $key_exists;
}