我不知道我错过了什么，但我一直在与 Twig 战斗，无法找出我错在哪里。
我有三个实体：产品、产品图片和类别
每个产品作为一个类别，一个类别有许多产品。每个产品都有许多图像。
我能够列出图像集合，这不是问题。
问题是我无法在我的 Twig 模板文件中获取每个产品的类别描述 ( product.categories.description )，如下所示：
{% extends '::base.html.twig' %}
{% block body %}
<div id="vitrines">
{{ debug products }}
{% for product in products %}
<div class="boxVitrine">
{% for image in product.images %}
{% if(image.oneOfType == 'thumb') %}
<img src="{{ asset('bundles/artevitrinesite/products/') }}{{ image.filename }}" />
{% endif %}
{% endfor %}
<div class="info">
<div class="container">
<div class="top">
<div class="code">
Cod: <span class="red1"><strong>{{ product.code }}</strong></span>
<br />{{ product.categories.description }}
</div>
<div class="price">{{ product.price | bigprice | raw }}</div>
</div>
</div>
</div>
</div>
{% endfor %}
</div>
{%endblock%}
所以，我有这两个类：
class Product
{
/**
* @var integer
*
* @ORM\Column(name="id", type="integer")
* @ORM\Id
* @ORM\GeneratedValue(strategy="AUTO")
*/
private $id;
/**
* @see Entity/Category
*
* @var integer $categoryId
*
* @ORM\ManyToOne(targetEntity="Category", inversedBy="products")
* @ORM\JoinColumn(name="category_id", referencedColumnName="id")
*
*/
protected $categoryId;
/**
*
* @var string $title
*
* @ORM\Column(name="title", type="string", length=255, nullable=false)
*
*/
protected $title;
/**
*
* @var string $description
*
* @ORM\Column(name="description", type="text", nullable=false )
*
*/
protected $description;
/**
*
* @var string $price
*
* @ORM\Column(name="price", type="decimal", precision=9, scale=2, nullable=false)
*
*/
protected $price;
/**
*
* @var string $status
*
* @ORM\Column(name="status", type="boolean")
*
*/
protected $status;
/**
*
* @var string $createdOn
*
* @ORM\Column(name="created_on", type="datetime")
*
*/
protected $createdOn;
/**
* @var \Doctrine\Common\Collections\ArrayCollection $images
* @ORM\OneToMany(targetEntity="ProductImage", mappedBy="productId")
*
*/
protected $images;
/**
* Constructor
*/
public function __construct()
{
$this->images = new \Doctrine\Common\Collections\ArrayCollection();
}
/**
* Get id
*
* @return integer
*/
public function getId()
{
return $this->id;
}
/**
* Set title
*
* @param string $title
* @return Product
*/
public function setTitle($title)
{
$this->title = $title;
return $this;
}
/**
* Get title
*
* @return string
*/
public function getTitle()
{
return $this->title;
}
/**
* Set description
*
* @param string $description
* @return Product
*/
public function setDescription($description)
{
$this->description = $description;
return $this;
}
/**
* Get description
*
* @return string
*/
public function getDescription()
{
return $this->description;
}
/**
* Set price
*
* @param float $price
* @return Product
*/
public function setPrice($price)
{
$this->price = $price;
return $this;
}
/**
* Get price
*
* @return float
*/
public function getPrice()
{
return $this->price;
}
/**
* Set status
*
* @param boolean $status
* @return Product
*/
public function setStatus($status)
{
$this->status = $status;
return $this;
}
/**
* Get status
*
* @return boolean
*/
public function getStatus()
{
return $this->status;
}
/**
* Set createdOn
*
* @param \DateTime $createdOn
* @return Product
*/
public function setCreatedOn($createdOn)
{
$this->createdOn = $createdOn;
return $this;
}
/**
* Get createdOn
*
* @return \DateTime
*/
public function getCreatedOn()
{
return $this->createdOn;
}
/**
* Set categoryId
*
* @param Category $categoryId
* @return Product
*/
public function setCategoryId(Category $categoryId = null)
{
$this->categoryId = $categoryId;
return $this;
}
/**
* Get categoryId
*
* @return Category
*/
public function getCategoryId()
{
return $this->categoryId;
}
/**
* Add images
*
* @param \ArteVitrine\BackendBundle\Entity\ProductImage $images
* @return Product
*/
public function addImage(ProductImage $images)
{
$this->images[] = $images;
return $this;
}
/**
* Remove images
*
* @param ProductImage $images
*/
public function removeImage(ProductImage $images)
{
$this->images->removeElement($images);
}
/**
* Get images
*
* @return \Doctrine\Common\Collections\Collection
*/
public function getImages()
{
return $this->images;
}
}
和：
class Category
{
/**
* @var integer
*
* @ORM\Column(name="id", type="integer")
* @ORM\Id
* @ORM\GeneratedValue(strategy="AUTO")
*/
private $id;
/**
*
* @var string $description
*
* @ORM\Column(name="description", type="text", nullable=false )
*
*/
protected $description;
/**
*
* @var string $status
*
* @ORM\Column(name="status", type="boolean")
*
*/
protected $status;
/**
*
* @var ArrayCollection $products
*
* @ORM\OneToMany(targetEntity="Category", mappedBy="categoryId")
*
*/
protected $products;
/**
* Get id
*
* @return integer
*/
public function getId()
{
return $this->id;
}
/**
* Set description
*
* @param string $description
* @return Category
*/
public function setDescription($description)
{
$this->description = $description;
return $this;
}
/**
* Get description
*
* @return string
*/
public function getDescription()
{
return $this->description;
}
/**
* Set status
*
* @param boolean $status
* @return Category
*/
public function setStatus($status)
{
$this->status = $status;
return $this;
}
/**
* Get status
*
* @return boolean
*/
public function getStatus()
{
return $this->status;
}
/**
* Constructor
*/
public function __construct()
{
$this->products = new ArrayCollection();
}
/**
* Add products
*
* @param Category $products
* @return Category
*/
public function addProduct(Category $products)
{
$this->products[] = $products;
return $this;
}
/**
* Remove products
*
* @param Category $products
*/
public function removeProduct(Category $products)
{
$this->products->removeElement($products);
}
/**
* Get products
*
* @return \Doctrine\Common\Collections\Collection
*/
public function getProducts()
{
return $this->products;
}
}
到目前为止，太好了，我只是不知道如何在循环中显示每个产品的类别信息，也不知道我是否以正确的方式进行操作。
提前致谢。