我正在尝试使用 JMS Serializer 包将 Doctrine2 实体序列化为 JSON。我已经设置好了所有东西，但是当我尝试将某些内容序列化为 JSON 时，我收到以下错误：
Fatal error: Cannot access private property Snow\FrontBundle\Entity\District::$id in E:\School\SocialGEO Augustus\Coding\socialgeo-php\vendor\jms\metadata\src\Metadata\PropertyMetadata.php on line 46
这是我的控制器代码：
public function indexAction() {
$em = $this->getDoctrine()->getManager();
$districts = $em->getRepository('SnowFrontBundle:District')->findAll();
$serializer = $this->get('jms_serializer');
echo $serializer->serialize($districts, 'json');
return array(
'districts' => $districts
);
}
最后，这是我的区实体：
<?php
namespace Snow\FrontBundle\Entity;
use Doctrine\ORM\Mapping as ORM;
/**
* District
*
* @ORM\Table(name="district")
* @ORM\Entity(repositoryClass="Snow\FrontBundle\Entity\Repositories\DistrictRepository")
*/
class District {
/**
* @var integer
*
* @ORM\Column(name="id", type="integer")
* @ORM\Id
* @ORM\GeneratedValue(strategy="AUTO")
*/
public $id;
/**
* @var string
*
* @ORM\Column(name="name", type="string", length=100)
*/
public $name;
/**
* @var string
*
* @ORM\Column(name="bigimage", type="string", length=100)
*/
public $bigimage;
/**
* @var string
*
* @ORM\Column(name="smallimage", type="string", length=100)
*/
public $smallimage;
/**
* @var string
*
* @ORM\Column(name="info", type="text")
*/
public $info;
/**
*
* @ORM\ManyToOne(targetEntity="City", inversedBy="districts")
* @ORM\JoinColumn(name="city_id", referencedColumnName="id")
*/
protected $city;
/**
*
* @ORM\OneToMany(targetEntity="District", mappedBy="city")
*/
protected $locations;
/**
*
* @var \Doctrine\Common\Collections\ArrayCollection $articles
* @ORM\ManyToMany(targetEntity="Article", mappedBy="districts")
*/
protected $articles;
/**
*
* @var \Doctrine\Common\Collections\ArrayCollection $workers
*
* @ORM\ManyToMany(targetEntity="User", inversedBy="districts")
* @ORM\JoinTable(name="workers_districts",
* joinColumns={@ORM\JoinColumn(name="district_id", referencedColumnName="id")},
* inverseJoinColumns={@ORM\JoinColumn(name="user_id", referencedColumnName="id")}
* )
*/
protected $workers;
/**
*
* @var \Doctrine\Common\Collections\ArrayCollection $userbookmarks
* @ORM\ManyToMany(targetEntity="User", mappedBy="favDistricts")
*/
protected $userbookmarks;
/**
* Get id
*
* @return integer
*/
public function getId() {
return $this->id;
}
/**
* Set name
*
* @param string $name
* @return District
*/
public function setName($name) {
$this->name = $name;
return $this;
}
/**
* Get name
*
* @return string
*/
public function getName() {
return $this->name;
}
/**
* Set info
*
* @param string $info
* @return District
*/
public function setInfo($info) {
$this->info = $info;
return $this;
}
/**
* Get info
*
* @return string
*/
public function getInfo() {
return $this->info;
}
/**
* Set city
*
* @param \Snow\FrontBundle\Entity\City $city
* @return District
*/
public function setCity(\Snow\FrontBundle\Entity\City $city = null) {
$this->city = $city;
return $this;
}
/**
* Get city
*
* @return \Snow\FrontBundle\Entity\City
*/
public function getCity() {
return $this->city;
}
/**
* Constructor
*/
public function __construct() {
$this->locations = new \Doctrine\Common\Collections\ArrayCollection();
}
/**
* Add locations
*
* @param \Snow\FrontBundle\Entity\District $locations
* @return District
*/
public function addLocation(\Snow\FrontBundle\Entity\District $locations) {
$this->locations[] = $locations;
return $this;
}
/**
* Remove locations
*
* @param \Snow\FrontBundle\Entity\District $locations
*/
public function removeLocation(\Snow\FrontBundle\Entity\District $locations) {
$this->locations->removeElement($locations);
}
/**
* Get locations
*
* @return \Doctrine\Common\Collections\Collection
*/
public function getLocations() {
return $this->locations;
}
/**
* Add articles
*
* @param \Snow\FrontBundle\Entity\Article $articles
* @return District
*/
public function addArticle(\Snow\FrontBundle\Entity\Article $articles) {
$this->articles[] = $articles;
return $this;
}
/**
* Remove articles
*
* @param \Snow\FrontBundle\Entity\Article $articles
*/
public function removeArticle(\Snow\FrontBundle\Entity\Article $articles) {
$this->articles->removeElement($articles);
}
/**
* Get articles
*
* @return \Doctrine\Common\Collections\Collection
*/
public function getArticles() {
return $this->articles;
}
/**
*
* @return string
*/
public function __toString() {
return $this->getName();
}
/**
* Add workers
*
* @param \Snow\FrontBundle\Entity\User $workers
* @return District
*/
public function addWorker(\Snow\FrontBundle\Entity\User $workers) {
$this->workers[] = $workers;
return $this;
}
/**
* Remove workers
*
* @param \Snow\FrontBundle\Entity\User $workers
*/
public function removeWorker(\Snow\FrontBundle\Entity\User $workers) {
$this->workers->removeElement($workers);
}
/**
* Get workers
*
* @return \Doctrine\Common\Collections\Collection
*/
public function getWorkers() {
return $this->workers;
}
/**
* Set bigimage
*
* @param string $bigimage
* @return District
*/
public function setBigimage($bigimage) {
$this->bigimage = $bigimage;
return $this;
}
/**
* Get bigimage
*
* @return string
*/
public function getBigimage() {
return $this->bigimage;
}
/**
* Set smallimage
*
* @param string $smallimage
* @return District
*/
public function setSmallimage($smallimage) {
$this->smallimage = $smallimage;
return $this;
}
/**
* Get smallimage
*
* @return string
*/
public function getSmallimage() {
return $this->smallimage;
}
/**
* Add userbookmarks
*
* @param \Snow\FrontBundle\Entity\User $userbookmarks
* @return District
*/
public function addUserbookmark(\Snow\FrontBundle\Entity\User $userbookmarks) {
$this->userbookmarks[] = $userbookmarks;
return $this;
}
/**
* Remove userbookmarks
*
* @param \Snow\FrontBundle\Entity\User $userbookmarks
*/
public function removeUserbookmark(\Snow\FrontBundle\Entity\User $userbookmarks) {
$this->userbookmarks->removeElement($userbookmarks);
}
/**
* Get userbookmarks
*
* @return \Doctrine\Common\Collections\Collection
*/
public function getUserbookmarks() {
return $this->userbookmarks;
}
}
有谁知道为什么会这样？如果我在我的实体中将所有内容都设置为公开，我似乎可以走得更远，但有些事情告诉我我不应该这样做。如果这样做，我会收到 Symfony2 错误消息：
An exception occurred while executing 'SELECT t0.id AS id1, t0.title AS title2, t0.path AS path3, t0.description AS description4, t0.createddate AS createddate5, t0.publisheddate AS publisheddate6, t0.deleteddate AS deleteddate7, t0.published AS published8, t0.url AS url9, t0.location_id AS location_id10, t0.user_id AS user_id11, t0.mediatype_id AS mediatype_id12 FROM media t0 WHERE t0.user_id = ?' with params {"1":6}:
SQLSTATE[42S22]: Column not found: 1054 Unknown column 't0.location_id' in 'field list'
提前感谢您提供的任何帮助！