Same name and namespace in other branches
  1. 10 core/lib/Drupal/Core/Form/FormBase.php \Drupal\Core\Form\FormBase
  2. 9 core/lib/Drupal/Core/Form/FormBase.php \Drupal\Core\Form\FormBase

Provides a base class for forms.

This class exists as a mid-point between dependency injection through ContainerInjectionInterface, and a less-structured use of traits which default to using the \Drupal accessor for service discovery.

To properly inject services, override create() and use the setters provided by the traits to inject the needed services.


public static function create($container) {
  $form = new static();
  // In this example we only need string translation so we use the
  // setStringTranslation() method provided by StringTranslationTrait.
  $form->setStringTranslation($container->get('string_translation'));
  return $form;
}

Alternately, do not use FormBase. A class can implement FormInterface, use the traits it needs, and inject services from the container as required.

Hierarchy

Expanded class hierarchy of FormBase

See also

\Drupal\Core\DependencyInjection\ContainerInjectionInterface

Related topics

144 files declare their use of FormBase
ActionAdminManageForm.php in core/modules/action/src/Form/ActionAdminManageForm.php
AddFormBase.php in core/modules/media_library/src/Form/AddFormBase.php
AjaxCssForm.php in core/modules/ckeditor/tests/modules/src/Form/AjaxCssForm.php
AjaxFormsTestAjaxElementsForm.php in core/modules/system/tests/modules/ajax_forms_test/src/Form/AjaxFormsTestAjaxElementsForm.php
AjaxFormsTestCommandsForm.php in core/modules/system/tests/modules/ajax_forms_test/src/Form/AjaxFormsTestCommandsForm.php

... See full list

File

core/lib/Drupal/Core/Form/FormBase.php, line 46

Namespace

Drupal\Core\Form
View source
abstract class FormBase implements FormInterface, ContainerInjectionInterface {
  use DependencySerializationTrait;
  use LinkGeneratorTrait;
  use LoggerChannelTrait;
  use MessengerTrait;
  use RedirectDestinationTrait;
  use StringTranslationTrait;
  use UrlGeneratorTrait;

  /**
   * The request stack.
   *
   * @var \Symfony\Component\HttpFoundation\RequestStack
   */
  protected $requestStack;

  /**
   * The config factory.
   *
   * Subclasses should use the self::config() method, which may be overridden to
   * address specific needs when loading config, rather than this property
   * directly. See \Drupal\Core\Form\ConfigFormBase::config() for an example of
   * this.
   *
   * @var \Drupal\Core\Config\ConfigFactoryInterface
   */
  protected $configFactory;

  /**
   * The route match.
   *
   * @var \Drupal\Core\Routing\RouteMatchInterface
   */
  protected $routeMatch;

  /**
   * {@inheritdoc}
   */
  public static function create(ContainerInterface $container) {
    return new static();
  }

  /**
   * {@inheritdoc}
   */
  public function validateForm(array &$form, FormStateInterface $form_state) {

    // Validation is optional.
  }

  /**
   * Retrieves a configuration object.
   *
   * This is the main entry point to the configuration API. Calling
   * @code $this->config('book.admin') @endcode will return a configuration
   * object in which the book module can store its administrative settings.
   *
   * @param string $name
   *   The name of the configuration object to retrieve. The name corresponds to
   *   a configuration file. For @code \Drupal::config('book.admin') @endcode,
   *   the config object returned will contain the contents of book.admin
   *   configuration file.
   *
   * @return \Drupal\Core\Config\ImmutableConfig
   *   A configuration object.
   */
  protected function config($name) {
    return $this
      ->configFactory()
      ->get($name);
  }

  /**
   * Gets the config factory for this form.
   *
   * When accessing configuration values, use $this->config(). Only use this
   * when the config factory needs to be manipulated directly.
   *
   * @return \Drupal\Core\Config\ConfigFactoryInterface
   */
  protected function configFactory() {
    if (!$this->configFactory) {
      $this->configFactory = $this
        ->container()
        ->get('config.factory');
    }
    return $this->configFactory;
  }

  /**
   * Sets the config factory for this form.
   *
   * @param \Drupal\Core\Config\ConfigFactoryInterface $config_factory
   *   The config factory.
   *
   * @return $this
   */
  public function setConfigFactory(ConfigFactoryInterface $config_factory) {
    $this->configFactory = $config_factory;
    return $this;
  }

  /**
   * Resets the configuration factory.
   */
  public function resetConfigFactory() {
    $this->configFactory = NULL;
  }

  /**
   * Gets the request object.
   *
   * @return \Symfony\Component\HttpFoundation\Request
   *   The request object.
   */
  protected function getRequest() {
    if (!$this->requestStack) {
      $this->requestStack = \Drupal::service('request_stack');
    }
    return $this->requestStack
      ->getCurrentRequest();
  }

  /**
   * Gets the route match.
   *
   * @return \Drupal\Core\Routing\RouteMatchInterface
   */
  protected function getRouteMatch() {
    if (!$this->routeMatch) {
      $this->routeMatch = \Drupal::routeMatch();
    }
    return $this->routeMatch;
  }

  /**
   * Sets the request stack object to use.
   *
   * @param \Symfony\Component\HttpFoundation\RequestStack $request_stack
   *   The request stack object.
   *
   * @return $this
   */
  public function setRequestStack(RequestStack $request_stack) {
    $this->requestStack = $request_stack;
    return $this;
  }

  /**
   * Gets the current user.
   *
   * @return \Drupal\Core\Session\AccountInterface
   *   The current user.
   */
  protected function currentUser() {
    return \Drupal::currentUser();
  }

  /**
   * Returns a redirect response object for the specified route.
   *
   * @param string $route_name
   *   The name of the route to which to redirect.
   * @param array $route_parameters
   *   (optional) Parameters for the route.
   * @param array $options
   *   (optional) An associative array of additional options.
   * @param int $status
   *   (optional) The HTTP redirect status code for the redirect. The default is
   *   302 Found.
   *
   * @return \Symfony\Component\HttpFoundation\RedirectResponse
   *   A redirect response object that may be returned by the controller.
   */
  protected function redirect($route_name, array $route_parameters = [], array $options = [], $status = 302) {
    $options['absolute'] = TRUE;
    return new RedirectResponse(Url::fromRoute($route_name, $route_parameters, $options)
      ->toString(), $status);
  }

  /**
   * Returns the service container.
   *
   * This method is marked private to prevent sub-classes from retrieving
   * services from the container through it. Instead,
   * \Drupal\Core\DependencyInjection\ContainerInjectionInterface should be used
   * for injecting services.
   *
   * @return \Symfony\Component\DependencyInjection\ContainerInterface
   *   The service container.
   */
  private function container() {
    return \Drupal::getContainer();
  }

  /**
   * Gets the logger for a specific channel.
   *
   * This method exists for backward-compatibility between FormBase and
   * LoggerChannelTrait. Use LoggerChannelTrait::getLogger() instead.
   *
   * @param string $channel
   *   The name of the channel. Can be any string, but the general practice is
   *   to use the name of the subsystem calling this.
   *
   * @return \Psr\Log\LoggerInterface
   *   The logger for the given channel.
   */
  protected function logger($channel) {
    return $this
      ->getLogger($channel);
  }

}

Members

Namesort ascending Modifiers Type Description Overrides
UrlGeneratorTrait::url Deprecated protected function Generates a URL or path for a specific route based on the given parameters.
UrlGeneratorTrait::setUrlGenerator Deprecated public function Sets the URL generator service.
UrlGeneratorTrait::getUrlGenerator Deprecated protected function Returns the URL generator service.
UrlGeneratorTrait::$urlGenerator protected property The url generator.
StringTranslationTrait::t protected function Translates a string to the current language or to a given language.
StringTranslationTrait::setStringTranslation public function Sets the string translation service to use. 2
StringTranslationTrait::getStringTranslation protected function Gets the string translation service.
StringTranslationTrait::getNumberOfPlurals protected function Returns the number of plurals supported by a given language.
StringTranslationTrait::formatPlural protected function Formats a string containing a count of items.
StringTranslationTrait::$stringTranslation protected property The string translation service. 1
RedirectDestinationTrait::setRedirectDestination public function Sets the redirect destination service.
RedirectDestinationTrait::getRedirectDestination protected function Returns the redirect destination service.
RedirectDestinationTrait::getDestinationArray protected function Prepares a 'destination' URL query parameter for use with \Drupal\Core\Url.
RedirectDestinationTrait::$redirectDestination protected property The redirect destination service. 1
MessengerTrait::setMessenger public function Sets the messenger.
MessengerTrait::messenger public function Gets the messenger. 29
MessengerTrait::$messenger protected property The messenger. 29
LoggerChannelTrait::setLoggerFactory public function Injects the logger channel factory.
LoggerChannelTrait::getLogger protected function Gets the logger for a specific channel.
LoggerChannelTrait::$loggerFactory protected property The logger channel factory service.
LinkGeneratorTrait::setLinkGenerator Deprecated public function Sets the link generator service.
LinkGeneratorTrait::l Deprecated protected function Renders a link to a route given a route name and its parameters.
LinkGeneratorTrait::getLinkGenerator Deprecated protected function Returns the link generator.
LinkGeneratorTrait::$linkGenerator protected property The link generator. 1
FormInterface::submitForm public function Form submission handler. 213
FormInterface::getFormId public function Returns a unique string identifying the form. 264
FormInterface::buildForm public function Form constructor. 191
FormBase::validateForm public function Form validation handler. Overrides FormInterface::validateForm 73
FormBase::setRequestStack public function Sets the request stack object to use.
FormBase::setConfigFactory public function Sets the config factory for this form.
FormBase::resetConfigFactory public function Resets the configuration factory.
FormBase::redirect protected function Returns a redirect response object for the specified route. Overrides UrlGeneratorTrait::redirect
FormBase::logger protected function Gets the logger for a specific channel.
FormBase::getRouteMatch protected function Gets the route match.
FormBase::getRequest protected function Gets the request object.
FormBase::currentUser protected function Gets the current user.
FormBase::create public static function Instantiates a new instance of this class. Overrides ContainerInjectionInterface::create 105
FormBase::container private function Returns the service container.
FormBase::configFactory protected function Gets the config factory for this form. 3
FormBase::config protected function Retrieves a configuration object.
FormBase::$routeMatch protected property The route match.
FormBase::$requestStack protected property The request stack. 1
FormBase::$configFactory protected property The config factory. 3
DependencySerializationTrait::__wakeup public function 2
DependencySerializationTrait::__sleep public function 1
DependencySerializationTrait::$_serviceIds protected property An array of service IDs keyed by property name used for serialization.
DependencySerializationTrait::$_entityStorages protected property An array of entity type IDs keyed by the property name of their storages.