drupal-form-api

Drupal Form API

Simple Form (FormBase)

// src/Form/MyForm.php
namespace Drupal\my_module\Form;

use Drupal\Core\Form\FormBase;
use Drupal\Core\Form\FormStateInterface;
use Symfony\Component\DependencyInjection\ContainerInterface;

final class MyForm extends FormBase {

  public function __construct(
    private readonly EntityTypeManagerInterface $entityTypeManager,
  ) {}

public static function create(ContainerInterface $container): static { return new static( $container->get('entity_type.manager'), ); }

public function getFormId(): string { return 'my_module_my_form'; }

public function buildForm(array $form, FormStateInterface $form_state): array { $form['name'] = [ '#type' => 'textfield', '#title' => $this->t('Name'), '#required' => TRUE, ]; $form['submit'] = [ '#type' => 'submit', '#value' => $this->t('Submit'), ]; return $form; }

public function submitForm(array &$form, FormStateInterface $form_state): void { $name = $form_state->getValue('name'); $this->messenger()->addStatus($this->t('Hello @name!', ['@name' => $name])); }

}

## Config Form (ConfigFormBase)

```php
final class MySettingsForm extends ConfigFormBase {

  protected function getEditableConfigNames(): array {
    return ['my_module.settings'];
  }

  public function getFormId(): string {
    return 'my_module_settings';
  }

  public function buildForm(array $form, FormStateInterface $form_state): array {
    $config = $this->config('my_module.settings');
    $form['enabled'] = [
      '#type' => 'checkbox',
      '#title' => $this->t('Enable feature'),
      '#default_value' => $config->get('enabled'),
    ];
    return parent::buildForm($form, $form_state);
  }

  public function submitForm(array &$form, FormStateInterface $form_state): void {
    $this->config('my_module.settings')
      ->set('enabled', $form_state->getValue('enabled'))
      ->save();
    parent::submitForm($form, $form_state);
  }

}

Common Form Elements

Type	Description
textfield	Single line text
textarea	Multi-line text
select	Dropdown
checkboxes	Multiple checkboxes
radios	Radio buttons
checkbox	Single checkbox
number	Numeric input
email	Email input
managed_file	Managed file upload
entity_autocomplete	Entity reference autocomplete
date	Date picker
details	Collapsible group
container	Non-visual wrapper
hidden	Hidden field
submit	Submit button