public static function ManagedFile::uploadAjaxCallback

#ajax callback for managed_file upload forms.

This ajax callback takes care of the following things:

• Ensures that broken requests due to too big files are caught.
• Adds a class to the response to be able to highlight in the UI, that a new file got uploaded.

Parameters

array $form: The build form.

\Drupal\Core\Form\FormStateInterface $form_state: The form state.

\Symfony\Component\HttpFoundation\Request $request: The current request.

Return value

\Drupal\Core\Ajax\AjaxResponse The ajax response of the ajax upload.

File

core/modules/file/src/Element/ManagedFile.php, line 180

Class

ManagedFile

Namespace

Code

public static function uploadAjaxCallback(&$form, FormStateInterface &$form_state, Request $request) {

  /** @var \Drupal\Core\Render\RendererInterface $renderer */
  $renderer = \Drupal::service('renderer');
  $form_parents = explode('/', $request->query
    ->get('element_parents'));

  // Sanitize form parents before using them.
  $form_parents = array_filter($form_parents, [
    Element::class,
    'child',
  ]);

  // Retrieve the element to be rendered.
  $form = NestedArray::getValue($form, $form_parents);

  // Add the special AJAX class if a new file was added.
  $current_file_count = $form_state
    ->get('file_upload_delta_initial');
  if (isset($form['#file_upload_delta']) && $current_file_count < $form['#file_upload_delta']) {
    $form[$current_file_count]['#attributes']['class'][] = 'ajax-new-content';
  }
  $status_messages = [
    '#type' => 'status_messages',
  ];
  $form['#prefix'] .= $renderer
    ->renderRoot($status_messages);
  $output = $renderer
    ->renderRoot($form);
  $response = new AjaxResponse();
  $response
    ->setAttachments($form['#attached']);
  return $response
    ->addCommand(new ReplaceCommand(NULL, $output));
}