Symfony 2-如何在Twig模板中显示已加入的条令实体

1. 如何在trick中检索实体数据？我选择了两个实体，新闻和评论，但在twitch中，我只能从新闻实体中获取数据。(例如："From Twig"(
2. 如何查看提取的实体对象中的内容(例如：Controller中的$fetched_news变量(。我尝试过：print_r($fetched_news(或{{dump(fetched_news}}}，但在第一个例子中，我得到了完整的代码屏幕，在第二个应用程序中，我被挂起了
3. 在"新闻"answers"评论"实体中，有一个名为"内容"的列。如何从这些列中获取数据？我在尝试这样的东西：

fetched_news.comments.content

或

fetched_news.news.content

我在许多页面上寻找答案，但找不到有趣的东西。

来自树枝：

{% for news in fetched_news %}
   <div class="col-md-5">
        <p class="news_title">{{ news.title }}</p>
        {{ (news.content|slice(0,600))|raw }}
         {{ news.ratePlus }} {# CAN'T GET THIS!#}
    {% else %}
{% endfor %}

来自控制器：

    public function indexAction()
{
    $em = $this->getDoctrine()->getManager();
    $query = $em->createQuery("SELECT n, a FROM BlogAdminBundle:News n JOIN n.comments a");
    $fetched_news = $query->getResult();

    return array('fetched_news' => $fetched_news);
}

来自Web档案器的代码

SELECT 
n0_.id AS id0, 
n0_.content AS content1, 
n0_.title AS title2, 
n0_.date_add AS date_add3, 
n0_.date_active AS date_active4, 
n0_.settings AS settings5, 
c1_.id AS id6, 
c1_.content AS content7, 
c1_.date_add AS date_add8, 
c1_.rate_plus AS rate_plus9, 
c1_.rate_minus AS rate_minus10, 
n0_.user_id AS user_id11, 
c1_.user_id AS user_id12, 
c1_.news_id AS news_id13 
FROM 
News n0_ 
INNER JOIN Comments c1_ ON n0_.id = c1_.news_id

谢谢你的帮助！

实体类注释：

 /**
 * @ORM'ManyToOne(targetEntity="News", inversedBy="comments")
 * @ORM'JoinColumn(name="news_id", referencedColumnName="id")
 */
protected $news;

实体类新闻：

 /**
 * @ORM'OneToMany(targetEntity="Comments", mappedBy="news")
 */
protected $comments;
public function __construct()
{
    $this->comments = new 'Doctrine'Common'Collections'ArrayCollection();
}

$repository = $this->getDoctrine()->getRepository('BlogAdminBundle:News');
$query = $repository->createQueryBuilder('p') 
    ->where('p.date_active < :date') 
    ->setParameter('date', new 'DateTime()) 
    ->getQuery(); 
$fetched_news = $query->getResult(); 

{% for news_article in fetched_news %} 
    {{ news_article.content }}
    {% for comment in news_article.comments %}
        {{ comment.content }}
    {% endfor %}
{% endfor %}