public static function NestedArray::keyExists

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 NestedArray::setValue() 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 NestedArray::getValue() 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 $array: The array with the value to check for.

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

Return value

bool TRUE if all the parent keys exist, FALSE otherwise.

See also

NestedArray::getValue()

3 calls to NestedArray::keyExists()
drupal_validate_form in drupal/core/includes/form.inc
Validates user-submitted form data in the $form_state array.
NestedArrayUnitTest::testKeyExists in drupal/core/tests/Drupal/Tests/Core/NestedArrayUnitTest.php
Tests existence of array key.
_form_builder_handle_input_element in drupal/core/includes/form.inc
Adds the #name and #value properties of an input element before rendering.

File

drupal/core/lib/Drupal/Component/Utility/NestedArray.php, line 262
Contains Drupal\Component\Utility\NestedArray.

Class

NestedArray
Provides helpers to perform operations on nested arrays and array keys of variable depth.

Namespace

Drupal\Component\Utility

Code

public static function keyExists(array $array, array $parents) {

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