Feature: #107343 - PSR-14 to manipulate form creation process 

Description 

A new PSR-14 event \TYPO3\CMS\Form\Event\BeforeFormIsCreatedEvent has been introduced. It serves as a direct replacement for the now removed hook $GLOBALS['TYPO3_CONF_VARS']['SC_OPTIONS']['ext/form']['beforeFormCreate'] .

The new event is dispatched immediately before a new form is created in the backend.

The event provides the following public properties:

• $form: The form definition array
• $formPersistenceIdentifier: The form persistence identifier used to store the new form

Example 

An example event listener could look like:

<?php

namespace MyVendor\MyExtension\Form\EventListener;

use TYPO3\CMS\Core\Attribute\AsEventListener;
use TYPO3\CMS\Form\Event\BeforeFormIsCreatedEvent;

final class MyEventListener
{
    #[AsEventListener('my_extension/before-form-is-created')]
    public function __invoke(BeforeFormIsCreatedEvent $event): void
    {
        $event->form['label'] = 'foo';
    }
}

Impact 

With the new BeforeFormIsCreatedEvent , it is now possible to modify a form before it is created.