How to set default value on Symfony3 EntityType?

Question

I'm trying to set a default value on EntityType select like this:

$builder
            ->add('town', EntityType::class, array(
                'label' => "TOWN",
                'class' => 'AppBundle:Town',
                'choice_label' => 'name',
                'choice_value' => 'id',
                'attr' => array('class' => 'form-control'),
                'placeholder' => 'CHOOSE_AN_OPTION',
                'required' => false,
                'data' => $this->em->getReference('AppBundle:Town', $options['attr']['town'])
            ));

I was trying to do it using data option. It works fot a ChoiceType, but not for EntityType. I tried to pass to the data option the town entity ID, Name and the entire object.

I create the form object from the controller:

$finder = $this->createForm(UserFinderType::class, null,
        array('attr' => array('role' => $this->getUser()->getRole(),
            'town'     => empty($params['town']) ? null : $townService->findOneById($params['town'])->getId() )));

When I pass Town ID or Name nothing happens, placeholder is shown. If I remove placeholder, blank option is selected.

When I pass entire Town object, this error is returned: Catchable Fatal Error: Object of class AppBundle\Entity\Town could not be converted to string

And, if I implement a __toString method, I get the same result that I get on ID or Name try.

Answer 1

You have to create __toString function in Town class:

AppBundle\Entity\Town

.................

public function __toString(){
    return $this->name; // If you have `name` field or u can return `id`
}