Symfony：如何强制Form-＆gt; handleRequest为空数字段不存在于帖子数据中

Question

我对How to stop Form->handleRequest from nulling fields that don't exist in post data提出了完全相反的问题。

我有一个动态表单，允许用户动态添加和删除表单中的字段。

表单允许用户创建新实体或编辑实体。在创作时，没有问题。但是，在版本上，当我使用$form->getData();时，我可以获得具有无效属性的实体。

例如：我有Vehicle个实体可以拥有以下值

• Type：自行车，摩托车，汽车
• Fuel：integer

表单将删除＆＃34; Fuel＆＃34;当我们选择＆＃34; Bicycle＆＃34;。但是，如果在版本之前，车辆是＆＃34; Car＆＃34;使用8 fuel，即使表单删除字段，$form->getData();也会返回类型为Bicycle和8 fuel的对象。

根据要求，这是FormType：

class VehicleType extends AbstractType
{

    public function buildForm(FormBuilderInterface $builder, array $options)
    {

        $formModifier = function (FormInterface $form, $fields = null, array $options) {

            foreach ($fields as $field_id => $field_value) {

                if ($field_id == 'vehicle') {
                    if ($field_value && ('car' == $field_value)) {
                        $form->add('gas');
                    } else {
                        $form->remove('gas');
                    }
                }
            }
        };

        $builder->addEventListener(
            FormEvents::PRE_SUBMIT,
            function (FormEvent $event) use ($formModifier, $options) {
                $formModifier($event->getForm(), $event->getData(), $options);
            }
        );

        $builder->addEventListener(
            FormEvents::PRE_SET_DATA,
            function (FormEvent $event) use ($formModifier, $options) {
                $vehicle = $event->getData();

                $formModifier($event->getForm(), array(
                    'vehicle' => $vehicle->getVehicle(),
                ), $options);
            }
        );

       $builder->add('vehicle', ChoiceType::class, array(
            'choices'  => array(
                'bicycle' => 'bicycle',
                'car' => 'car',
            )
        ));

        $builder->add('add', SubmitType::class);
    }
}

实体并不特别：

class Vehicle
{
    /**
     * @var int
     *
     * @ORM\Column(name="id", type="integer")
     * @ORM\Id
     * @ORM\GeneratedValue(strategy="AUTO")
     *
     */
    private $id;
    /**
     * @var int
     *
     * @ORM\Column(name="vehicle", type="string", length=255)
     */
    private $vehicle;

    /**
     * @var string
     *
     * @ORM\Column(name="gas", type="smallint", nullable=true)
     */
    private $gas;


   (...)

然后，控制器：

/**
 * @Route("/vehicle-add", name="vehicle_add")
 */
public function vehicleAddAction(Request $request)
{
    $vehicle = new Vehicle();

    $form = $this->createForm(VehicleType::class, $vehicle);
    $form->handleRequest($request);

    if ($form->isSubmitted() && $form->isValid()) {
        $vehicle = $form->getData();
        $em = $this->getDoctrine()->getManager();

        $em->persist($vehicle);
        $em->flush();
    }

    return $this->render('default/vehicle-add.html.twig', array(
        'form' => $form->createView(),
    ));
}


/**
 * @Route("/vehicle-edit", name="vehicle_edit")
 */
public function vehicleEditAction(Request $request)
{

    $vehicle = $this->getDoctrine()->getRepository('AppBundle:Vehicle')->findOneBy(array('id' => 1));

    $form = $this->createForm(VehicleType::class, $vehicle);
    $form->handleRequest($request);

    if ($form->isSubmitted() && $form->isValid()) {
        $vehicle = $form->getData();

        $em = $this->getDoctrine()->getManager();
        $em->persist($vehicle);
        $em->flush();
    }

    return $this->render('default/vehicle-edit.html.twig', array(
        'form' => $form->createView(),
    ));
}