forms - 评论博客创建不起作用的symfony

您好，我想在博客中添加评论，一切都很好，但没有显示错误，但是当我单击“提交”时，没有任何反应，我的意思是它没有在数据库中添加它，我不知道我在想什么，这是我在控制器中拥有的

public function addCommentAction(Request $request, $id)
    {
        $user=$this->getUser();
        if($user==null)
            return $this->redirectToRoute('fos_user_security_login');
        $add_comment = new CommentaireBlog();
        $em = $this->getDoctrine()->getManager();
        $blog = $em->getRepository(Blog::class)->find($id);
        $add_comment->setBlog($blog);
        $add_comment->setUser($user);
        $add_comment->setDate( new \DateTime());

        $form = $this->createFormBuilder($add_comment)

            ->add('contenu', TextareaType::class)
            ->getForm();

        if ($request->getMethod() == 'POST') {
            $form->handleRequest($request);

            if ($form->isSubmitted() && $form->isValid()) {
                $add_comment = $form->getData();
                $em = $this->getDoctrine()->getEntityManager();
                $em->persist($add_comment);
                $em->flush();

                return $this->redirect($this->generateUrl('blog_details'));
            }
        }

        return $this->render('blog/details.html.twig', array(
            'form' => $form->createView(),
            'comment' => $add_comment,
            'blog' => $blog,
        ));

    }

这就是我在blog.yml中所拥有的

comment_new:
    path:     /{id}/details
    defaults: { _controller: "BlogBundle:Blog:addComment" }
    methods:  [GET, POST]

最后是树枝页面

<div class="comments-form">
                                <h4 class="comments-title">Leave A Reply</h4>

                                    <!-- .row -->
                                    <form action="{{ path('comment_new', { 'id': blog.id }) }}" method="post" >

                                        <textarea id="form_comment" name="form[comment]" required="required" class="form-control comments-textarea" placeholder="Comments*"></textarea>

                                        <input type="submit" class="btn btn-default" />


                                </form>
                            </div>
                        </div>