Encapsulates the caching of a form and its form state. Hierarchy class \Drupal\Core\Form\

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

Stores information about the state of a subform. In the context of Drupal's Form API, a subform is a form definition array that will be nested

Provides an interface for form building and processing. Hierarchy interface \Drupal\Core\Form\

public FormState::addRebuildInfo($property, $value) Adds

public BrokenPostRequestException::

The class resolver. Type:

protected FormBase::config($name) Retrieves

public FormStateDecoratorBase::isRedirectDisabled()