Rendering forms

Staying on forms for just a bit longer, let's quickly learn how to render forms programmatically. We have already seen how to map a form to a route definition so that the page being built contains the form when accessing the route path. However, there are times when we need to render a form programmatically, either inside a Controller or a block, or wherever you want. We can do this using the FormBuilder service.

The form builder can be injected using the form_builder service key or used statically via the shorthand:

$builder = \Drupal::formBuilder(); 

Once we have it, we can build a form, like so:

$form = $builder->getForm('Drupal\hello_world\Form\SalutationConfigurationForm'); 

In the preceding code, $form will be a render array of the form that we can return, for example, inside a Controller. We'll talk more about render arrays a bit later on, and you'll understand how they get turned into actual form markup. However, for now, this is all you need to know about rendering forms programmatically—you get the form builder and request from it the form using the fully qualified name of the form class.

With this, we can close the parenthesis on forms.