如何在表单有效时将Symfony中的表单数据映射到对象？

Question

Imagine example form in Symfony:

public function buildForm(FormBuilderInterface $builder)
{
    $builder
        ->add('email', EmailType::class, [
            'constraints' => 
                new NotBlank(),
                new IsUnique(),
            ],
        ])
        ->add('password', PasswordType::class, [
            'constraints' => 
                new NotBlank(),
                new IsStrongEnough(),
            ],
        ])
}

Now when I submit the form and make sure it's valid, I'd like the $form->getData() to return my DTO called CreateAccountCommand:

final class CreateAccountCommand
{
    private $email;
    private $password;

    public function __construct(string $email, string $password)
    {
        $this->email = $email;
        $this->password = $password;
    }

    public function getEmail(): string
    {
        return $this->email;
    }

    public function getPassword(): string
    {
        return $this->password;
    }
}

Example controller:

$form = $this->formFactory->create(CreateAccountForm::class);
$form->handleRequest($request);

if ($form->isSubmitted() && $form->isValid()) {
    $this->commandBus->dispatch($form->getData());

    return new JsonResponse([]);
}

I cannot use this class directly using the data_class, because the form obviously expects the model to have setters that allow null values. The form itself works perfectly well, so is the validation.

I tried using the Data mapper method, but the mapFormsToData method is invoked, before the validation.

Is this possible at all? Or am I supposed to get the data as array and create the object outside the form?

Answer 1

Here is how I'm used to handle form with Symfony 4.1

Let's assume you want a simple add form

The Form

class CreateAccountForm extends AbstractType
{
    public function buildForm(FormBuilderInterface $builder)
    {
        //same method than yours
    }

    public function configureOptions(OptionsResolver $resolver)
    {
        $resolver->setDefaults(array('data_class' => 'App\Entity\CreateAccountCommand'));
    }
}

The controller

public function add(Request $request)
{
    $createAccountCommand = new CreateAccountCommand();

    //The object is "injected" to the form, that way, it's mapped when submitted
    $form = $this->get('form.factory')->create(CreateAccountForm::class, $createAccountCommand);

    //Form was submitted
    if ($request->isMethod('POST') && $form->handleRequest($request)->isValid())
    {
        //no need to getData(), the object $createAccountCommand is directly mapped to the form and can be used as is
        $em = $this->getDoctrine()->getManager();
        //persist, convert to json, or whatever
        $em->persist($createAccountCommand);
        $em->flush();

        return ($this->redirectToRoute('someRoute'));
    }

    //form not submitted, or has been submit with errors (isValid() == false)
    return ($this->render('account/add.html.twig',
            array('form' => $form->createView())));
}