Mastering Drupal 8

Other form types

In addition to the FormBase class, there are two other built-in types of form: ConfirmFormBase and ConfigFormBase. In order to create a form of these types, you would use Drupal Console to create the form and then change the class to extend the appropriate FormBase class. You would use the ConfirmFormBase class to verify the user intended to perform an action. In Drupal 7, this was handled using the confirm_form function; in Drupal 8, you create your form class and extend the ConfirmFormBase class. When you extend ConfirmFormBase, you will be implementing ConfirmFormInterface, which contains some functions that are not implemented on the base class. At the very least, you need to write the getCancelUrl function, which returns ...