以多对多关系的形式设置multi =='false'symfony2

Question

I have a many-to-many relationship between two entities A and B.

So when adding a form, in order to add entityA to entityB , I am doing the following:

$builder          
    ->add('entityAs', 'entity', array(
      'class'    => 'xxxBundle:EntityA',
      'property' => 'name',
      'multiple' => true,
    ));}

And everything is alright.

But depending on the field type of entityA, I want to sometimes set 'multiple' to false, so I'm doing the following :

if($type=='a'){
    $builder          
        ->add('entityAs', 'entity', array(
          'class'    => 'xxxBundle:entityA',
          'property' => 'name',
          'multiple' => true,
        ));}

else {
    $builder          
        ->add('entityAs', 'entity', array(
          'class'    => 'xxxBundle:entityA',
          'property' => 'name',
          'multiple' => false,

        ));
}

This gives me the following error:

Catchable Fatal Error: Argument 1 passed to Doctrine\Common\Collections\ArrayCollection::__construct() must be an array, object given, called in C:\wamp\www\Symfony\vendor\doctrine\orm\lib\Doctrine\ORM\UnitOfWork.php on line 519 and defined in C:\wamp\www\Symfony\vendor\doctrine\common\lib\Doctrine\Common\Collections\ArrayCollection.php line 48 

Can anybody help me?

Answer 1

In EntityA, you have something like this, right?

public function setEntitiesB($data)
{
    $this->entitiesB = $data ;
}

Now because you can also receive single value instead of array of values, you need something like this:

public function setEntitiesB($data)
{
    if ( is_array($data) ) {
        $this->entitiesB = $data ;
    } else {
        $this->entitiesB->clear() ;
        $this->entitiesB->add($data) ;
    }
}

Answer 2

i would check the entityA value in the controller and depending on it create different forms.

in controller:

if ($entityA->getType() == 'a') { 
    $form = new FormB(); // form with multiple true
} else {
    $form = new FormA(); // form with multiple false
}