Symfony 2.8 Catchable Fatal Error: Object of class ... could not be converted to string (one to many and many to one)

Question

这是我的第一个问题，如有遗漏请见谅

我定义了 2 个实体：产品和类别。

<?php

namespace Backend\AdminBundle\Entity;

use Doctrine\Common\Collections\ArrayCollection;
use Doctrine\ORM\Mapping as ORM;

/**
 * Category
 *
 * @ORM\Table(name="category")
 * @ORM\Entity(repositoryClass="Backend\AdminBundle\Repository\CategoryRepository")
 */
class Category
{
    /**
     * @ORM\OneToMany(targetEntity="Product", mappedBy="category")
     */

    public function __construct()
    {
        $this->products = new ArrayCollection();
    }


    /**
     * @var int
     *
     * @ORM\Column(name="id", type="integer")
     * @ORM\Id
     * @ORM\GeneratedValue(strategy="AUTO")
     */
    private $id;

    /**
     * @var string
     *
     * @ORM\Column(name="name", type="string", length=100, unique=true)
     */
    private $name;

    /**
     * @var int
     *
     * @ORM\Column(name="status", type="integer")
     */
    private $status;

    /**
     * @var int
     *
     * @ORM\Column(name="parent_id", type="integer")
     */
    private $parentId;


    /**
     * Get id
     *
     * @return integer 
     */
    public function getId()
    {
        return $this->id;
    }

    /**
     * Set name
     *
     * @param string $name
     * @return Category
     */
    public function setName($name)
    {
        $this->name = $name;

        return $this;
    }

    /**
     * Get name
     *
     * @return string 
     */
    public function getName()
    {
        return $this->name;
    }

    /**
     * Set status
     *
     * @param integer $status
     * @return Category
     */
    public function setStatus($status)
    {
        $this->status = $status;

        return $this;
    }

    /**
     * Get status
     *
     * @return integer 
     */
    public function getStatus()
    {
        return $this->status;
    }

    /**
     * Set parentId
     *
     * @param integer $parentId
     * @return Category
     */
    public function setParentId($parentId)
    {
        $this->parentId = $parentId;

        return $this;
    }

    /**
     * Get parentId
     *
     * @return integer 
     */
    public function getParentId()
    {
        return $this->parentId;
    }
}

和

use Doctrine\ORM\Mapping as ORM;

/**
 * Product
 *
 * @ORM\Table(name="product")
 * @ORM\Entity(repositoryClass="Backend\AdminBundle\Repository\ProductRepository")
 */
class Product
{
    /**
     * @ORM\ManyToOne(targetEntity="Category", inversedBy="products")
     * @ORM\JoinColumn(name="category_id", referencedColumnName="id")
     */
    private $category;

    /**
     * @var int
     *
     * @ORM\Column(name="id", type="integer")
     * @ORM\Id
     * @ORM\GeneratedValue(strategy="AUTO")
     */
    private $id;

    /**
     * @var string
     *
     * @ORM\Column(name="name", type="string", length=255)
     */
    private $name;

    /**
     * @var string
     *
     * @ORM\Column(name="short_description", type="string", length=255)
     */
    private $shortDescription;

    /**
     * @var string
     *
     * @ORM\Column(name="full_description", type="text")
     */
    private $fullDescription;

    /**
     * @var float
     *
     * @ORM\Column(name="price", type="float")
     */
    private $price;

    /**
     * @var int
     *
     * @ORM\Column(name="status", type="integer")
     */
    private $status;

    /**
     * @var int
     *
     * @ORM\Column(name="category_id", type="integer")
     */
    private $categoryId;


    /**
     * Get id
     *
     * @return integer 
     */
    public function getId()
    {
        return $this->id;
    }

    /**
     * Set name
     *
     * @param string $name
     * @return Product
     */
    public function setName($name)
    {
        $this->name = $name;

        return $this;
    }

    /**
     * Get name
     *
     * @return string 
     */
    public function getName()
    {
        return $this->name;
    }

    /**
     * Set shortDescription
     *
     * @param string $shortDescription
     * @return Product
     */
    public function setShortDescription($shortDescription)
    {
        $this->shortDescription = $shortDescription;

        return $this;
    }

    /**
     * Get shortDescription
     *
     * @return string 
     */
    public function getShortDescription()
    {
        return $this->shortDescription;
    }

    /**
     * Set fullDescription
     *
     * @param string $fullDescription
     * @return Product
     */
    public function setFullDescription($fullDescription)
    {
        $this->fullDescription = $fullDescription;

        return $this;
    }

    /**
     * Get fullDescription
     *
     * @return string 
     */
    public function getFullDescription()
    {
        return $this->fullDescription;
    }

    /**
     * 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 integer $status
     * @return Product
     */
    public function setStatus($status)
    {
        $this->status = $status;

        return $this;
    }

    /**
     * Get status
     *
     * @return integer 
     */
    public function getStatus()
    {
        return $this->status;
    }

    /**
     * Set categoryId
     *
     * @param integer $categoryId
     * @return Product
     */
    public function setCategoryId($categoryId)
    {
        $this->categoryId = $categoryId;

        return $this;
    }

    /**
     * Get categoryId
     *
     * @return integer 
     */
    public function getCategoryId()
    {
        return $this->categoryId;
    }

    /**
     * Set category
     *
     * @param \Backend\AdminBundle\Entity\Category $category
     * @return Product
     */
    public function setCategory(\Backend\AdminBundle\Entity\Category $category = null)
    {
        $this->category = $category;

        return $this;
    }

    /**
     * Get category
     *
     * @return \Backend\AdminBundle\Entity\Category 
     */
    public function getCategory()
    {
        return $this->category;
    }
}

我已经设法正确设置它们之间的关系，因为类别有很多产品，而产品只有一个类别。

我成功地为类别创建了我的 CRUD 并且它有效。

我能够为产品创建我的 CRUD，访问索引路由并且工作正常。

问题是当我尝试创建新产品时出现以下异常：

Catchable Fatal Error: Object of class Backend\AdminBundle\Entity\Category could not be converted to string

这是我的第一个 Symfony 测试项目，除了完全是菜鸟之外，我还被困住了。我知道我一定是遗漏了一些非常明显的东西，但我不知道是什么。

我正在使用 Symfony 2.8。

我做错了什么？

Answer 1

为您的 Category 实体定义一个魔术方法 __toString()。

示例，按如下方式进行：

public function __toString() 
{
    return $this->getName();
}

Symfony 2.8 Catchable Fatal Error: Object of class ... could not be converted to string (one to many and many to one)

Symfony 2.8 Catchable Fatal Error: Object of class ... could not be converted to string (one to many and many to one)

php

symfony

orm

crud

foreign-key-relationship