如何在索引操作中显示多个对一个关系对象

我正在尝试创建一个基于symfony的论坛。在索引页上，我需要向用户显示他们可以选择进入的部分。然而，每个部分都有类别，所有这些都需要显示在一个视图中。它应该是这样的。

• Section1
  • category1
  • category2
• Section2
  • category3

等。

我正在遵循symblog.co.uk教程，并尝试根据他们的博客/评论的例子来做，有一个简单的问题，他们在显示动作中定义评论，每个博客都有$comments变量，我需要我的类别可以从$sections变量访问。对于每个Section用户必须能够读取类别和添加新的

我的文件是这样的

index action，基本视图，我写的所有内容都发生在这里

{% block body %}
    IndexAction of Page Controller

    <form action="{{ path("EpiForumBundle_section_create") }}" method="post" {{ form_enctype(form) }} class="section">
        {{ form_errors(form) }}
        {{ form_row(form.name) }}
                {{ form_rest(form) }}
        <input type="submit" value="Submit" />
    </form>
        <table>
            <th>date created
            <th>name
    {% for section in sections %}
                <tr>
                    <td>
            <div class="date"><time datetime="{{ section.created|date('c') }}">{{ section.created|date('l, F j, Y') }}</time></div>
                    </td>
                    <td>    
                <p><span class="highlight">{{ section.name }}</span></p>
                    </td>
                </tr>
    {% else %}
        <p>There are no sections for this forum</p>
    {% endfor %}
    </table>
{% endblock %}

页面控制器

<?php
namespace Epi'ForumBundle'Controller;
use Symfony'Bundle'FrameworkBundle'Controller'Controller;
use Epi'ForumBundle'Entity'Section;
use Epi'ForumBundle'Form'SectionType;
class PageController extends Controller
{
    public function indexAction()
    {       
            $section = new Section();
                $form = $this->createForm(new SectionType(), $section);
        $em = $this->getDoctrine()
                   ->getEntityManager();
        $sections = $em->getRepository('EpiForumBundle:Section')
                    ->getLatestSections();
        return $this->render('EpiForumBundle:Page:index.html.twig', array('sections' => $sections, 'form' => $form->createView()));
    }
}

部分控制器

<?php
namespace Epi'ForumBundle'Controller;
use Symfony'Bundle'FrameworkBundle'Controller'Controller;
use Epi'ForumBundle'Entity'Section;
use Epi'ForumBundle'Form'SectionType;
class SectionController extends Controller
{
    public function createAction()
    {
        $section = new Section();
            $form = $this->createForm(new SectionType(), $section);
            $em = $this->getDoctrine()->getManager();
            $request = $this->getRequest();
            if($request->getMethod() == 'POST'){
                $form->bind($this->getRequest());/*or  $form->handleRequest($request); depends on symfony version */
                $em->persist($section);
                $em->flush();
                return $this->redirect("/");
            }
            return $this->redirect("/");
    }
}

部分类型:

<?php
namespace Epi'ForumBundle'Form;
use Symfony'Component'Form'AbstractType;
use Symfony'Component'Form'FormBuilderInterface;
use Symfony'Component'OptionsResolver'OptionsResolverInterface;
class SectionType extends AbstractType
{
        /**
     * @param FormBuilderInterface $builder
     * @param array $options
     */
    public function buildForm(FormBuilderInterface $builder, array $options)
    {
        $builder
            ->add('name');
    }
    /**
     * @param OptionsResolverInterface $resolver
     */
    public function setDefaultOptions(OptionsResolverInterface $resolver)
    {
        $resolver->setDefaults(array(
            'data_class' => 'Epi'ForumBundle'Entity'Section'
        ));
    }
    /**
     * @return string
     */
    public function getName()
    {
        return 'epi_forumbundle_section';
    }
}

那么现在我把这些分类表单放在哪里呢?如何编写这些表单来了解section_id?

/**
 *
 * @ORM'ManyToOne(targetEntity="Acme'DemoBundle'Entity'Teacher", inversedBy="divisions")
 * @ORM'JoinColumn(nullable=false)
 */
private $teacher;

/**
 * @ORM'OneToMany(targetEntity="Acme'DemoBundle'Entity'Division", mappedBy="teacher", cascade={"remove"})
 */
private $divisions;

public function __construct()
{
    parent::__construct(); (optional)
    $this->divisions = new 'Doctrine'Common'Collections'ArrayCollection();
}

/**
 * Set teacher
 * 
 * @param Acme'DemoBundle'Entity'Teacher $teacher
 */
public function setTeacher('Acme'DemoBundle'Entity'Teacher $teacher)
{
    $this->teacher = $teacher;
    $teacher->setDivision($this);
}

->add('section', 'entity', array('class' => 'YourBundle:Section', 'property' => 'name','label' => 'Section'))