扶手：的has_many，也HAS_ONE一个不同的名称 [英] Rails: has_many, but also has_one by a different name

问题描述

比方说，一个用户有许多文件 s和一个文件他们目前正在努力。我该如何重新present这在轨？

Let's say a User has many Documents, and a single Document they're currently working on. How do I represent this in rails?

我想说 current_user.current_document = Document.first （有或没有在CURRENT_文件前）和拥有它不改变 CURRENT_USER .documents 集合。

I want to say current_user.current_document = Document.first (with or without current_ in front of document) and have it not change the current_user.documents collection.

这是我有：

class Document < ActiveRecord::Base
  belongs_to :user
end

class User < ActiveRecord::Base
  has_many :documents
  has_one :document
end

问题是，当我说 current_user.document = some_document ，它会删除该文件previously存储在 current_user.document 从 current_user.documents 。这是有道理的，由于 HAS_ONE 关系，即文件有，但不是我想要的。如何解决呢？

the problem is that when I say current_user.document = some_document, it removes the document previously stored in current_user.document from current_user.documents. This makes sense due to the has_one relationship that Document has, but isn't what I want. How do I fix it?

推荐答案

您需要更改模型，以

class Document < ActiveRecord::Base
  belongs_to :user
end

class User < ActiveRecord::Base
  has_many :documents

  # you could also use :document, but I would recommend this:
  belongs_to :current_document, :class_name => "Document"
end

P.S。但要注意的循环节约。如果你创建一个新用户（但不保存它尚未），并设置 current_document ，然后保存，你可能会得到堆栈溢出或其他疯狂错误的用户。

P.S. But beware of cyclic saves. If you create a new User (and don't save it yet) and set current_document and then save the User you might get stack overflows or other crazy errors.

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