如果数组中存在实体，则显示添加或删除按钮

我有实体旅行，收藏夹和用户，每个用户都可以将旅行添加到他的收藏夹列表中。

当显示所有旅行的列表时，我希望如果旅行已经在用户收藏夹中，则显示按钮（删除），如果不在列表中，则显示（添加到收藏夹）。

在操作控制器中，我做了一个查询构建器来获取当前经过身份验证的用户的所有收藏夹的列表，并将结果放在（$favorite）中。

    public function listAction($page, Request $request)
    {
    $em = $this->getDoctrine()->getManager();
    // code of boutton add to or remove from favorite
    $user = $this->getUser(); // this is a function to verify if user is AUTHENTICATED_REMEMBERED
    if($user) {
    $favorite = $em->getRepository('ProjectTravelBundle:Favorite')->getFavoriteByUser($user);
    }
    else{
    $favorite = '';
    }
    $paginator  = $this->get('knp_paginator');
    $qb = $em->getRepository('ProjectTravelBundle:Travel')->getListTravelsFrontend();
    $nb = $qb->getQuery()->getResult();
    $pagination = $paginator->paginate(
        $qb,
        $request->query->get('page', $page),10);

    return $this->render('ProjectFrontendBundle:Travel:travel-list-view.html.twig',array(
        'pagination' => $pagination,
        'nb' => $nb,
        'favorite' =>$favorite, // list of favorites of current user 
    ));
}

我考虑的解决方案是测试旅行是否在数组（收藏夹）中，因此显示 boutton 删除，如果没有，则显示 boutton 添加，但我未能在 show.twig 中执行此操作

{% for travel in pagination %}
//..................
{% if is_granted('IS_AUTHENTICATED_REMEMBERED') %}
{% if travel.id not in favorite %}
    <span><a href="{{ path('frontend_travel_add_favorite', {'id': travel.id} ) }}" class="pull-right button btn-small red">Add to favorite</a></span>
{% else %}
    <span><a href="{{ path('frontend_travel_delete_favorite', {'id': favorite.id} ) }}" class="pull-right button btn-small red">Remove from</a></span>
{% endif %}
// if user is not AUTHENTICATED_REMEMBERED
{% else %}
<span><a href="{{ path('frontend_travel_add_favorite', {'id': travel.id} ) }}" class="pull-right button btn-small red">Add to favorite</a></span>
{% endif %}
//..........
{% endfor %}

存储库：查询生成器

    // get list of favorite of current user
    public function getFavoriteByUser($user)
    {
        $qb = $this->createQueryBuilder('f')
            ->Where('f.user = '.$user);
        return $qb->getQuery()->getResult();
    }

更新

收藏夹实体

class Favorite
{
/**
 * @var integer
 *
 * @ORM'Column(name="id", type="integer")
 * @ORM'Id
 * @ORM'GeneratedValue(strategy="AUTO")
 */
private $id;
/**
 * @ORM'ManyToOne(targetEntity="Project'UserBundle'Entity'User")
 * @ORM'JoinColumn(nullable=false)
 */
protected $user;
/**
 * @ORM'ManyToOne(targetEntity="Project'TravelBundle'Entity'Travel", inversedBy="favorites")
 * @ORM'JoinColumn(nullable=false)
 */
protected $travel;

/**
 * Get id
 *
 * @return integer 
 */
public function getId()
{
    return $this->id;
}
/**
 * Set user
 *
 * @param 'Project'UserBundle'Entity'User $user
 * @return Favorite
 */
public function setUser('Project'UserBundle'Entity'User $user)
{
    $this->user = $user;
    return $this;
}
/**
 * Get user
 *
 * @return 'Project'UserBundle'Entity'User 
 */
public function getUser()
{
    return $this->user;
}

/**
 * Set travel
 *
 * @param 'Project'TravelBundle'Entity'Travel $travel
 * @return Favorite
 */
public function setTravel('Project'TravelBundle'Entity'Travel $travel)
{
    $this->travel = $travel;
    return $this;
}
/**
 * Get travel
 *
 * @return 'Project'TravelBundle'Entity'Travel 
 */
public function getTravel()
{
    return $this->travel;
}
}

旅游实体

class Travel
{
/....
/**
 * @ORM'OneToMany(targetEntity="Project'TravelBundle'Entity'Favorite", mappedBy="travel", cascade={"remove"})
 */
private $favorites; 

public function __construct()
{
    $this->favorites = new 'Doctrine'Common'Collections'ArrayCollection();
}
/...........
/**
 * Add favorites
 *
 * @param 'Project'TravelBundle'Entity'Favorite $favorites
 * @return Travel
 */
public function addFavorite('Project'TravelBundle'Entity'Favorite $favorites)
{
    $this->favorites[] = $favorites;
    $favorites->setTravel($this);
    return $this;
}
/**
 * Remove favorites
 *
 * @param 'Project'TravelBundle'Entity'Favorite $favorites
 */
public function removeFavorite('Project'TravelBundle'Entity'Favorite $favorites)
{
    $this->favorites->removeElement($favorites);
}
/**
 * Get favorites
 *
 * @return 'Doctrine'Common'Collections'Collection 
 */
public function getFavorites()
{
    return $this->favorites;
}