Creating a Form Type Class

Introduction: The Power of Forms

Forms are everywhere. Login boxes, search fields, admin tooling, checkout steps — if your app lets humans type things, congrats, you’re in Form Land. And even though front-ends today might be buzzing with Ajax, Turbo, and fancy JavaScript libraries, the core job is still the same old classic: grab some data, check it, and do something meaningful with it. And that’s exactly where Symfony's Form component steps in wearing a cape. It wrangles request data, applies validation, protects you from CSRF villains, and generally keeps you from hand-crafting HTML inputs like it's 1995.

So let's get our hands dirty and create our first form!

Getting Started with the Course Code

To follow along, download the course code from this page and extract it. Inside, you'll find a start/ directory containing the course project. Open its README.md file and you'll find instructions to get the website up and running. I've already done this part, so I'll just launch the built-in Symfony web server in my terminal with:

symfony serve -d

Then, open the site by holding Cmd and clicking at the URL in the output. Welcome to Starshop, your one-stop shop for all your essential Starship parts — hyperdrive couplers, warp coils, left-handed quantum stabilizers, you know, the usual stuff. Let's head over to Parts page.

Business is booming in our little corner of the Galaxy, so now we need to create new Starship parts in the admin area. I've already added a link to "Create a new part". The only issue is that the actual form is still a work in progress. Let's fix that!

Installing the Symfony Form Component

Before we can build forms, we need the Symfony Form component itself. Install it using:

symfony composer require form

Running git status will show us that the installation brought some new config files. Perfect, now we're ready to start building. We could build the form manually, field by field, line by line, but that's a surefire way to drain our life force.

Creating a Form Type Class with Maker

Instead, let's let Maker bundle help us. Run:

symfony console make:form

Here's a quick tip: if you haven't installed the Form component yet, Maker will tell you exactly what command you need to run. Maker is like that friendly coworker who gently reminds you that you forgot to run composer install... again.

You can name the form whatever you like, but it's common practice to end form classes with "Type". For instance, since we're creating Starship parts, I'll name this one StarshipPartType. Next, maker will ask if we want to map the form to an entity. We certainly do in this case, so choose the StarshipPart entity. That's the entity we'll be creating with this form. Once that's done, maker will create a new file in the src/Form/ directory. Now, open it up in PhpStorm.

The class extends AbstractType, which comes from the Form component we just installed. Maker has also conveniently added a form field for every property on the entity. We don't really want users editing timestamps though (unless we're looking for time travel paradoxes), so let's get rid of those fields. Below, in the configureOptions(), you'll spot the data_class option set to the StarshipPart::class. That binds this form to that entity. Quite handy!

Creating the Form Object with createForm()

Now it's time to create a form object using our new form type. The controller behind this page is AdminController and the action is newStarshipPart. Let's open it up. Inside, we'll create a form object with $form = $this->createForm....

Symfony kindly provides two useful methods, createForm() and createFormBuilder(). The latter lets you build a form right inside the controller, perfect for quick prototypes. However, best practice is to create a dedicated form type class, like the one we just crafted.

So, we'll stick with $this->createForm(). Pass our StarshipPartType::class, and voila, we've got a form! If we dd($form) below and refresh the page, you'll see it's a Form object — a fully-fledged PHP object with all the logic. Let's pass it to the template with 'form' => $form and remove the dd($form) statement. Now we can render it in the template.

Form Object in PHP vs FormView one in Twig

But there's a twist! If you first dump it in Twig with {{ dump(form) }} and refresh the page again, you'll see that it's a FormView object instead. That's Symfony quietly doing you a favor converting the internal Form object into a simpler view model that can be rendered in Twig. They might look similar, but remember, they're technically different objects.

Older versions of Symfony required developers to explicitly pass the FormView object to the template for rendering. That's why you might see $form->createView() calls in legacy projects.

But with the latest version of Symfony, this is handled automatically, so you don't need to worry about it. In fact, to make it work properly with Turbo, you should now always pass the internal form object.

Okay, up next, we'll render and submit the form for real. Are you ready to dive in?