Symfony3 Render multiple time same form - forms

Question

I would like to render the same form multiple times to handle the same action for two different tabs.
The problem is that when I try, only the form of the first tab is shown, event if I change the id and name of the form.
I found out it's the expected behavior of symfony, but I still need it to work.
I found that it may works with a collection but don't get how it would work.
twig:
{{ form(contactForm, {'attr': {'id': 'contactFormId' ~ Client.Id}, 'name': "contactFormName" ~ Client.Id})}}
Form:
$this->contactForm = $this->createFormBuilder($contact, array('allow_extra_fields' =>true))
->add('Nom', TextType::class, array('mapped'=>false))
->add('Prenom', TextType::class, array('mapped'=>false))
->add('Telephone', TextType::class, array(
'label' => 'Téléphone'))
->add('Email', TextType::class)
->add('Ajouter', SubmitType::class)
->getForm();

Answer 1

It is an older question, but I just came across it facing a similar situation. I wanted to have multiple versions of one form object in a list view. For me the solution was to move the createView() call on the form object to the view instead of calling it in the controller. This is kind of a dirty solution regarding separation of concerns, but I thought to post it so it may help others anyway.
My controller action looks like this:
/**
* #Route("", name="cart_show")
* #Method("GET")
*/
public function showAction(Request $request)
{
/** #var CartInterface $cart */
$cart = $this->get('rodacker.cart');
$deleteForm = $this->createDeleteForm();
return $this->render(
'AppBundle:Cart:show.html.twig',
['cart' => $cart, 'deleteForm' => $deleteForm]
);
// ...
private function createDeleteForm()
{
return $this->createForm(
OrderItemDeleteType::class,
null,
[
'action' => $this->generateUrl('cart_remove_item'),
'method' => 'DELETE',
]
);
}
}
and in the view I set the form variable by calling the createView function on the form variable (deleteForm) passed from the controller:
{% for item in items %}
{% set form = deleteForm.createView %}
{{ form_start(form) }}
{{ form_widget(form.item, {'value': item.image.filename}) }}
<button type="submit" class="btn btn-xs btn-danger" title="Artikel entfernen">
<i class="fa fa-trash-o"></i> entfernen
</button>
{{ form_end(form) }}
{% endfor %}

Answer 2

Once you render a Symfony form, the same form will not render again.
I would suggest creating a form class and calling Controller::createForm() multiple times to create the desired amount of Form instances; you can call isSubmitted etc. on all forms independently.
http://symfony.com/doc/current/book/forms.html#creating-form-classes