class MyType extends AbstractType
{
 
    /**
     * @param FormBuilderInterface $builder
     * @param array $options
     */
    public function buildForm(FormBuilderInterface $builder,array $options)
    {
       ...
    }
 
    /**
     * @param OptionsResolverInterface $resolver
     */
    public function setDefaultOptions(OptionsResolverInterface $resolver)
    {
        $resolver->setDefaults(array(
            'data_class' => 'LogicielBundle\Entity\FichierGroup','intention' => $this->getName() . '_token'
        ));
    }

但是在POST_SUBMIT事件中,我想返回null(没有实体).
我测试了这个但不工作：

$builder->addEventListener(FormEvents::POST_SUBMIT,function(FormEvent $event) {
        .... my condition ...
        $event->setData(null);
    });

你可以帮我吗 ？谢谢 ：)