获取子实体返回null而不是arrayCollection对象 [英] Get child entities returns null instead of arrayCollection object

问题描述

我有两个具有oneToMany关系的实体：

发布实体：

  ... 
 oneToMany：
图像：
 mappedBy：post 
 targetEntity：Shop\Bundle\ManagementBundle\Entity\Image 
  

图像实体：

  ... 
 manyToOne：
 post：
 targetEntity：Shop\Bundle\ManagementBundle\Entity\Post 
 inversedBy：images 
 joinColumn：
 onDelete：cascade 
  

与 $实体实例 Post ，当我在做 $ entity-> getImages（）时，我收到的东西如下： / p>

 对象（Doctrine\ORM\PersistentCollection）[65] 
 private'snapshot'=> 
 array（size = 0）
 empty 
 private'owner'=> 
 object（Acme\Bundle\ImageUpBundle\Entity\Post）[54] 
 private'id'=> int 41 
 private'title'=> string'kbd'（length = 3）
 private'images'=> 
& object（Doctrine\ORM\PersistentCollection）[65] 
 private'association'=> 
数组（size = 15）
'fieldName'=> string'images'（length = 6）
'targetEntity'=>字符串'Shop\Bundle\ManagementBundle\Entity\Image'（length = 38）
'mappedBy'=> string'post'（length = 4）
'type'=> int 4 
'inversedBy'=> null 
'isOwningSide'=> boolean false 
'sourceEntity'=> string'Shop\Bundle\ManagementBundle\Entity\Post'（length = 37）
'fetch'=> int 2 
'cascade'=> 
 array（size = 0）
 empty 
'isCascadeRemove'=> boolean false 
'isCascadePersist'=> boolean false 
'isCascadeRefresh'=> boolean false 
'isCascadeMerge'=> boolean false 
'isCascadeDetach'=> boolean false 
'orphanRemoval'=> boolean false 
 private'em'=> 
 .... 
  

但是现在我不幸得到 null 。

我真的很尽力找出可能导致这个问题的原因。您的帮助非常感激。

编辑：

给定一个整数$ id，我使用以下方式获取一个Post实体：

  $ em = $ this-> getDoctrine（） - > getManager（） ; 
 $ entity = $ em-> getRepository（'ShopManagementBundle：Post'） - > find（$ id）; 
  

我成功获取了Post实体的所有属性，除了图像。

解决方案

这里有解决我的问题的东西：

1-我在配置文件中收集了一个 oneToMany 参数之间的一对多关联。换句话说，而不是：

  oneToMany：
图像：
 targetEntity .... 
 .... 
 oneToMany：
消息：
 targerEntity ... 
 .... 
  

我会有：

  oneToMany：
图片： 
 targerEntity ... 
 .... 
消息：
 targerEntity ... 
 .... 
  / pre> 
 
 
 
 
我再次使用 app / console生成实体doc：gen：entities 使唯一的构造函数构造两个 ArrayCollection 。
 
 
 
 
 < blockquote> 
 
  / ** 
 *构造函数
 * / 
 public function __construct（）
 {
 $ this-> messages = new \Doctrine\Common\Collections\ArrayCollection（）; 
 $ this-> images = new \Doctrine\Common\Collections\ArrayCollection（）; 
} 
  
 
 
现在，当我打电话 $ em-> getRepository（'ShopManagementBundle：Post） - > find（$ id）我有子实体（ Images ）当数据库中存在具体的记录，而不是Null时，附加到我的父实体（ Post ）。当我使用新的Post（）删除新的实体时，我有空的ArrayCollection而不是空。
 
 
 
我知道这个答案是缺乏编程逻辑，似乎是任意的努力，但是我写这个是为了分享这个例子突然出现这个问题（正如我所说）。我希望它有帮助。
 
I have two entities with a oneToMany relationship:

Post entity:
...
oneToMany:
  images:
    mappedBy: post
    targetEntity: Shop\Bundle\ManagementBundle\Entity\Image
Image entity:
...
    manyToOne:
        post:
            targetEntity: Shop\Bundle\ManagementBundle\Entity\Post
            inversedBy: images
            joinColumn:
                onDelete: cascade
With $entity instance of Post, when I was doing $entity->getImages(), I was receiving something like:
     object(Doctrine\ORM\PersistentCollection)[65]
      private 'snapshot' => 
        array (size=0)
          empty
      private 'owner' => 
        object(Acme\Bundle\ImageUpBundle\Entity\Post)[54]
          private 'id' => int 41
          private 'title' => string 'kbd' (length=3)
          private 'images' => 
            &object(Doctrine\ORM\PersistentCollection)[65]
      private 'association' => 
        array (size=15)
          'fieldName' => string 'images' (length=6)
          'targetEntity' => string 'Shop\Bundle\ManagementBundle\Entity\Image' (length=38)
          'mappedBy' => string 'post' (length=4)
          'type' => int 4
          'inversedBy' => null
          'isOwningSide' => boolean false
          'sourceEntity' => string 'Shop\Bundle\ManagementBundle\Entity\Post' (length=37)
          'fetch' => int 2
          'cascade' => 
            array (size=0)
              empty
          'isCascadeRemove' => boolean false
          'isCascadePersist' => boolean false
          'isCascadeRefresh' => boolean false
          'isCascadeMerge' => boolean false
          'isCascadeDetach' => boolean false
          'orphanRemoval' => boolean false
      private 'em' =>
....
But now i unfortunately get null. 

I really did all my best to figure out what might cause such issue. Your help is much appreciated.

Edit:

given an in integer $id, I fetch a Post entity using:
$em = $this->getDoctrine()->getManager();
$entity = $em->getRepository('ShopManagementBundle:Post')->find($id);
I successfully get all the attributes of Post entity except from images.
解决方案
Well here are the things that solved my issue:

1- I gathered all One To Many associations under one oneToMany parameter in config file. In other words, instead of having:
oneToMany: 
  images:
     targetEntity....
     ....
oneToMany:
   messages:
      targerEntity...
      ....
I would have:
oneToMany:
   images:
      targerEntity...
      ....
   messages:
      targerEntity...
      ....



I generated entities again using app/console doc:gen:entities making the only one constructor constructs the two ArrayCollections.



/**
     * Constructor
     */
    public function __construct()
    {
        $this->messages = new \Doctrine\Common\Collections\ArrayCollection();
        $this->images = new \Doctrine\Common\Collections\ArrayCollection();
    }

Now when I call $em->getRepository('ShopManagementBundle:Post)->find($id) I have the child entities (Images) attached to my parent entity (Post) when concrete records exist in database, and not Null. When I insantiate a new entity using new Post(), I have empty ArrayCollection and not Null.

I know this answer is lacking of programming logic and seems arbitrary effort, but I write it in the sake of sharing in the case someone encounters suddenly this problem (As I did). I hope it helps.

                        
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