Symfony array as Form Collection

Question

I have been stuck with a problem in Symfony for days, and can't find anything on google.

I have two tables.

Account:

AppBundle\Entity\Account:
type: entity
fields:
    name:
        type: string
        nullable: true
        length: 255
oneToMany:
    towns:
        targetEntity: AppBundle\Entity\Town
        mappedBy: owner
        cascade: ['persist']

Town:

AppBundle\Entity\Town:
type: entity
fields:
    name:
        type: string
        nullable: true
        length: 255
manyToOne:
    owner:
        targetEntity: AppBundle\Entity\Account
        inversedBy: towns

And I have an array with names:

$names = ['New York','Berlin'];

I want a form in which the user can check a name from the array (Check boxes). When the user checks 'New York' and submits the form, I want a new entity Town with 'New York' in the name field. If the user unchecks 'New York', I want the entity removed.

So far I tried it with EntityType , CollectionType , and ChoiceType . The Best I can get is with ChoiceType.

public function buildForm(FormBuilderInterface $builder, array $options)
{
    $builder
        ->add('towns', ChoiceType::class,
            [
                'choices' =>
                    [
                        new Town('New York'),
                        new Town('Berlin'),
                    ],
                'choice_label' => function (Town $town, $key, $index) {
                    return $town->getName();
                },
                'choice_value' => function (Town $town) {
                    return $town->getName();
                },
                'expanded' => TRUE,
                'multiple' => TRUE,
                'required' => FALSE,
            ]
        );
}

But it will add a new entity every time the user submits the form for any town that is checked and it does not remove the non checked one...

Answer 1

Don't use an array, store the towns in the database.
Then set the towns field type to EntityType .

->add(
    'towns',
    EntityType::class,
    [
        'class' => Town::class,
        'multiple' => true,
        'expanded' => true,
        'required' => false,
    ]
)

Add this method to your Town class to display the name automatically everywhere it has to be converted to string:

/**
 * @return string
 */
public function __toString()
{
    return $this->name;
}

---

If the idea with the array was to filter the choices displayed to choose towns, you could use it in the query_builder option:

public function buildForm(FormBuilderInterface $builder, array $options)
{
    $names = ['New York', 'Berlin']; // Or pass it from the controller in $options

    $builder
        ->add('towns',
            EntityType::class,
            [
                'class' => Town::class,
                'query_builder' => function (EntityRepository $er) use ($names) {
                    return $er->createQueryBuilder('town')
                        ->where('town.name IN (:names)')
                        ->setParameter('names', $names);
                },
                'multiple' => true,
                'expanded' => true,
                'required' => false,
            ]
        );
}