许多自我参考的中等细节 [英] doctrine2 many to many self referencing with intermediate details

问题描述

我想创建一个自引用实体，但有一个关于关系的描述（可能还有其他信息）。一个例子就是社交网络应用中的朋友 - 人A（实体）可以与Person B（实体）链接，但是他们的关系可以被描述为朋友兄弟叔叔等。

从Doctrine文档中，一个类可以使用以下链接表进行自引用：

 <？php 
 / ** @Entity * / 
 class User 
 {
 // ... 
 
 / ** 
 * @ManyToMany（targetEntity =User，mappedBy =myFriends）
 * / 
 private $ friendsWithMe; 
 
 / ** 
 * @ManyToMany（targetEntity =User，inversedBy =friendsWithMe）
 * @JoinTable（name =friends，
 * joinColumns = {@ JoinColumn（name =user_id，referencedColumnName =id）}，
 * inverseJoinColumns = {@ JoinColumn（name =friend_user_id，referencedColumnName =id）} 
 * 
 * / 
 private $ myFriends; 
 
 public function __construct（）{
 $ this-> friendsWithMe = new \Doctrine\Common\Collections\ArrayCollection（）; 
 $ this-> myFriends = new \Doctrine\Common\Collections\ArrayCollection（）; 
} 
 
 // ... 
} 
  

然而，似乎您可以使用此方法添加属性。

问题是，是否有一种在单个类中处理这个问题的方法（即用户.php） - 或者实际上要做一个链接类 - 像UserLink.php？我开始关系时遇到了一个链接类：

  class UserLink 
 {
 // ... 
 
 / ** 
 * @ ORM\Column（type =text，nullable = true）
 * / 
 protected $关系; //是兄弟，叔叔等
 
 / ** 
 * @ ORM\ManyToOne（targetEntity =User，inversedBy =links）
 * @ ORM\ JoinColumn（name =user_id，referencedColumnName =id）
 * @var类型
 * / 
 private $ user; 
} 
  

但我不知道接下来会发生什么？

研究stackoverflow我发现类似的问题，但更多关于直接链接。

Doctrine2：使用额外列处理多对多的最佳方式参考表格

需要帮助了解原则许多多个自引用代码

解决方案

已解决它像这样：

User.php

  / ** 
 * @ ORM\OneToMany（targetEntity =UserLink，mappedBy =user）
 * / 
 private $ relations; 
  

UserLink.php

  / ** 
 * @ ORM\Column（type =text，nullable = true）
 * / 
 protected $ relationship; 
 
 / ** 
 * @ ORM\ManyToOne（targetEntity =User，inversedBy =relations）
 * @ ORM\JoinColumn（name =user_ud ，referencedColumnName =id）
 * / 
 protected $ user; 
 
 / ** 
 * @ ORM\ManyToOne（targetEntity =User）
 * @ ORM\JoinColumn（name =related_user_id，referencedColumnName =id ）
 * / 
 protected $ relateduser; 
  

它需要一些控制器和模型中的代码，但效果很好。它允许用户调用getRelations：

  {％for user.relations％} 
 {{link。 relateduser.name}}（{{link.relationship}}）
 {％endfor％} 
  

I would like to create a self-referencing entity, but with a description (and possibly other information) about the relationship. An example of this would be friends in a social network application - Person A (entity) can link with Person B (entity), however their relationship could be described as "friend" "brother" "uncle" etc.

From the Doctrine documentation a class can be self referencing with a link table using the following:

<?php
/** @Entity */
class User
{
    // ...

    /**
     * @ManyToMany(targetEntity="User", mappedBy="myFriends")
     */
    private $friendsWithMe;

    /**
     * @ManyToMany(targetEntity="User", inversedBy="friendsWithMe")
     * @JoinTable(name="friends",
     *      joinColumns={@JoinColumn(name="user_id", referencedColumnName="id")},
     *      inverseJoinColumns={@JoinColumn(name="friend_user_id", referencedColumnName="id")}
     *      )
     */
    private $myFriends;

    public function __construct() {
        $this->friendsWithMe = new \Doctrine\Common\Collections\ArrayCollection();
        $this->myFriends = new \Doctrine\Common\Collections\ArrayCollection();
    }

    // ...
}

however it doesn't seem that you can add properties using this method.

The question is, is there a way to handle this in a single class (i.e. User.php) - or would one actually have to make a "link" class - like UserLink.php? I kind of got stuck making a link class when I started on the relations:

class UserLink
{
    // ...

    /**
     * @ORM\Column(type="text", nullable=true)
     */
    protected $relationship; // being brother, uncle etc

    /**
     * @ORM\ManyToOne(targetEntity="User", inversedBy="links")
     * @ORM\JoinColumn(name="user_id", referencedColumnName="id")
     * @var type
     */
    private $user;
}

But I am not sure what happens next...?

Researching on stackoverflow I found similar questions, but more about direct linking.

Doctrine2: Best way to handle many-to-many with extra columns in reference table

Need help understanding Doctrine many to many self referencing code

解决方案

Solved it like this:

User.php

/**
 * @ORM\OneToMany(targetEntity="UserLink", mappedBy="user")
 */
private $relations;    

UserLink.php

/**
 * @ORM\Column(type="text", nullable=true)
 */
protected $relationship;

/**
 * @ORM\ManyToOne(targetEntity="User", inversedBy="relations")
 * @ORM\JoinColumn(name="user_ud", referencedColumnName="id")
 */
protected $user;

/**
 * @ORM\ManyToOne(targetEntity="User")
 * @ORM\JoinColumn(name="related_user_id", referencedColumnName="id")
 */
protected $relateduser;

It requires a bit more code in the controller and model, but works quite well. It enables the user to call getRelations:

{% for link in user.relations %}
    {{ link.relateduser.name }} ({{ link.relationship }})
{% endfor %}

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