Provides an interface for building AJAX form responses. Hierarchy interface \Drupal\Core\Form\

Defines element value callables which are safe to run even when the form state has an invalid CSRF token. Excluded from this list on purpose:

public ConfirmFormInterface::getQuestion()

If TRUE, the form was submitted programmatically, usually invoked via

public FormStateInterface::setErrorByName($name, $message = '')

public &FormStateInterface::getGroups()

The config factory. Subclasses should use the self::config() method, which may be overridden to address specific needs when loading config,

public FormCache::__construct($root, KeyValueExpirableFactoryInterface $key_val

public static SubformState::createForSubform(array &$subform, array &$parent_form

public FormAjaxException::getForm() Gets