Symfony2 - why the integer value in the hidden field is not recognized as integer?

Question

I have a custom form type for a "Rating" entity in my Symfony2 project. It has a value field, that is integer. Then, I created the form for this entity. Here follows the code:

class RatingType extends AbstractType
{
  public function buildForm(FormBuilder $builder, array $options){
     $builder->add('value', 'hidden', array('data' => 113));
  }

  public function getDefaultOptions(array $options){
     return array(
         'data_class' => 'Acme\ArticleBundle\Entity\Rating',
     );
  }    

  public function getName() {
     return 'spesax_productbundle_pratingtype';
  }
}

When I press the submit button in my html page, the form is not validated and a "not an integer" error message is displayed on the screen!
Why Symfony2 doesn't cast the value 113 to integer? What can I do to solve this problem?

Answer 1

When using the type hidden instead of integer in your FormType, symfony does not know what to expect from the field, so it assumes a string. When binding the form to the entity, the hidden field gets stored into the entity field as a string.

Validating the entity fails if you validate with type="integer", as the value is not an integer but a string which could be casted to an integer (Saving it will work because doctrine looks if it can convert to the given type).

The trick is to use type="numeric" in your entity validation annotation. This will check if the field can be transformed into an integer, not if the value is a real integer right now.