如何从特定主题中获取当前 id？

Question

我有一个主题论坛，每个主题都可以被其他用户评论。我创建的关系是：

class Comment
{
    /**
     * @ORM\ManyToOne(targetEntity="AppBundle\Entity\Topic", inversedBy="comments")
     */
    private $topic;
}

还有班级主题：

class Topic
{
     /**
     * @ORM\OneToMany(targetEntity="AppBundle\Entity\Comment", mappedBy="topic")
     * @ORM\JoinColumn(name="comment_id", referencedColumnName="id")
     */
    private $comments;  
}

问题是，当我创建评论时，cmets 表中的 topic_id 列为空。我不确定如何获取当前主题 ID 并将其设置为评论。这是我在 CommentController 中的 addCommentAction() 函数：

     /**
     * @Route("/comment/add", name="comment_add")
     * @param Request $request
     * @return \Symfony\Component\HttpFoundation\Response
     */
    public function addCommentAction(Request $request)
    {
        $comment = new Comment();

        $form = $this->createForm(CommentType::class, $comment);
        $form->handleRequest($request);

        if ($form->isValid()) {

            $comment->setDateCreated(new \DateTime());

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


            $this->addFlash(
                'notice',
                'Comment Added Successfully !'
            );
        }
        return $this->render('comments/comment.add.html.twig', array(
            'commentsForm' => $form->createView()
        ));
    }

树枝模板中的路径：

<a href="{{ path('comment_add') }}" class="btn btn-lg btn-default">Leave a Comment</a>

Answer 1

快完成了 :) 试试关注

如果主题已经存在

$em = $this->getDoctrine()->getManager();
$topic = $em->getRepository('YouBundle:Topic')->find( $topic_id );

if(false === $topic instanceof topic )
{
 // not found ...
}

$comment = new Comment();
$comment->setTopic( $topic )
// createForm....

如果没有，则在 DB 中查找一个，创建一个

$topic = new Topic();
$comment = new Comment();
$comment->setTopic( $topic );

UPD： 正如@Jakub Matczak 所说。您可能必须在表单中添加一个带有 topic_id 的隐藏字段，因为您不想获得包含所有可用主题的下拉列表。

在 buildForm 方法中的 CommentForm 类中

$builder->add('topic', HiddenType:class, []);

Answer 2

您必须在评论实体上设置主题。在您的路由中，您必须添加主题的 id，然后 Symfony 将自动获取带有 ParamConverter 的主题实体

类似的东西应该可以工作：

/**
 * @Route("/{id}/comment/add", name="comment_add")
 * @param Request $request
 * @return \Symfony\Component\HttpFoundation\Response
 */
public function addCommentAction(Request $request, Topic $topic)
{
    $comment = new Comment();
    $comment->setTopic($topic);

    $form = $this->createForm(CommentType::class, $comment);
    $form->handleRequest($request);

    if ($form->isValid()) {

        $comment->setDateCreated(new \DateTime());

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


        $this->addFlash(
            'notice',
            'Comment Added Successfully !'
        );
    }
    return $this->render('comments/comment.add.html.twig', array(
        'commentsForm' => $form->createView()
    ));
}

Answer 3

注意事项： $form = $this->createForm(CommentType::class, $comment); 不应该是“评论”吗？我在您的描述中没有看到任何 CommentType 类。

此外，当您添加新评论时，您需要以某种方式传递 topicId。 我会为“/comment/add”做一个 POST 操作，并在正文中发送主题 ID。

 // Rest of the imports...
 use Sensio\Bundle\FrameworkExtraBundle\Configuration\Method;

 /**
 * @Route("/comment/add", name="comment_add")
 * @Method({"POST"})
 * @param Request $request
 * @return \Symfony\Component\HttpFoundation\Response
 */
public function addCommentAction(Request $request)
{
    $comment = new Comment();

    $form = $this->createForm(CommentType::class, $comment);
    $form->handleRequest($request);

    if ($form->isValid()) {

        $comment->setDateCreated(new \DateTime());

        $em = $this->getDoctrine()->getManager();

        $topicId = $request->request->get('topicId');
        $topic = $em->getRepository('Bundle:Topic')->find($topicId); // retrieve the topic id from the corresponding repository of the topic entity
        $comment->setTopic($topic); // setting the topic to the comment

        $em->persist($comment);
        $em->flush();


        $this->addFlash(
            'notice',
            'Comment Added Successfully !'
        );
    }
    return $this->render('comments/comment.add.html.twig', array(
        'commentsForm' => $form->createView()
    ));
}

You need also to add a repository from which you will retrieve the Topic objects. You need just an empty class named TopicRepository that should extend EntityRepository from Doctrine.

除此之外，您还应该在从客户端执行 POST 请求时发送“topicId”。