形式：避免设置为null，非现场提交(Form: Avoid setting null to non

我有一个简单的模型（简化源）：

class Collection
{
    public $page;
    public $limit;
}

而表单类型：

class CollectionType extends AbstractType
{
    public function buildForm(FormBuilderInterface $builder, array $options)
    {
        $builder->add('page', 'integer');
        $builder->add('limit', 'integer');
    }

    public function setDefaultOptions(OptionsResolverInterface $resolver)
    {
        $resolver->setDefaults(array(
            'data_class' => 'FSC\Common\Rest\Form\Model\Collection',
        ));
    }
}

我的控制器：

public function getUsersAction(Request $request)
{
    $collection = new Collection();
    $collection->page = 1;
    $collection->limit = 10;

    $form = $this->createForm(new CollectionType(), $collection)
    $form->bind($request);

    print_r($collection);exit;
}

当我POST /users/?form[page]=2&form[limit]=20 ，则响应是我期望：

Collection Object
(
    [page:public] => 2
    [limit:public] => 20
)

现在，当我POST /users/?form[page]=3 ，则响应是：

Collection Object
(
    [page:public] => 3
    [limit:public] =>
)

limit变得无效，因为它未提交。

我想获得

Collection Object
(
    [page:public] => 3
    [limit:public] => 10 // The default value, set before the bind
)

问 ：我怎样才能改变形式的行为，所以它忽略非提交的值？

Answer 1:

如果仅仅是一个（GET参数）的参数问题，你可以定义默认值到路由文件

route_name:
pattern: /users/?form[page]={page}&form[limit]={limit}
defaults: { _controller: CompanyNameBundleName:ControllerName:ActionName, 
                         limit:10 }

的另一种方式可以是使用一个钩子 （即PRE_BIND ）并手动更新该值到该事件。 这样，你就没有了“逻辑”铺展成多段代码。

最后的代码 - 由阿德里安建议 - 将

<?php

use Symfony\Component\Form\FormEvent;
use Symfony\Component\Form\FormFactoryInterface;
use Symfony\Component\EventDispatcher\EventSubscriberInterface;
use Symfony\Component\Form\FormEvents;

class IgnoreNonSubmittedFieldSubscriber implements EventSubscriberInterface
{
    private $factory;

    public function __construct(FormFactoryInterface $factory)
    {
        $this->factory = $factory;
    }

    public static function getSubscribedEvents()
    {
        return array(FormEvents::PRE_BIND => 'preBind');
    }

    public function preBind(FormEvent $event)
    {
        $submittedData = $event->getData();
        $form = $event->getForm();

        // We remove every child that has no data to bind, to avoid "overriding" the form default data
        foreach ($form->all() as $name => $child) {
            if (!isset($submittedData[$name])) {
                $form->remove($name);
            }
        }
    }
}

Answer 2:

这里是原来的答案的修改。 该解决方案的最重要的好处是验证现在可以执行如表单提交将始终是完整的，这意味着有错误冒泡和这样的没有问题。

需要注意的是对象字段名称必须与表单字段名称对于此代码工作。

<?php
namespace Acme\DemoBundle\Form;

use Symfony\Component\Form\FormEvent;
use Symfony\Component\Form\FormFactoryInterface;
use Symfony\Component\EventDispatcher\EventSubscriberInterface;
use Symfony\Component\Form\FormEvents;

class FillNonSubmittedFieldsWithDefaultsSubscriber implements EventSubscriberInterface
{
    private $factory;

    public function __construct(FormFactoryInterface $factory)
    {
        $this->factory = $factory;
    }

    public static function getSubscribedEvents()
    {
        return array(FormEvents::PRE_BIND => 'preBind');
    }

    public function preBind(FormEvent $event)
    {
        $submittedData = $event->getData();
        $form = $event->getForm();

        // We complete partial submitted data by inserting default values from object
        foreach ($form->all() as $name => $child) {
            if (!isset($submittedData[$name])) {
                $obj = $form->getData();

                $getter = "get".ucfirst($name);
                $submittedData[$name] = $obj->$getter();
            }
        }
        $event->setData($submittedData);

    }
}

文章来源: Form: Avoid setting null to non submitted field