Backbone.js的：建模belongs_to的关系 [英] Backbone.js: Modeling a belongs_to relationship

问题描述

说我有一个帖子集合骨干的应用程序。所有职位都属于一个博客。创建一个新的职位要求我知道博客是属于： POST /博客/ 42 /岗位

Say I have a Backbone application with a Posts collection. All posts belong to a Blog. Creating a new post requires me to know the Blog it belongs to: POST /blog/42/posts

下面是我想出了迄今为止 - 请告诉我，如果有一个更好的解决方案：

Here is what I came up with so far -- please tell me if there is a better solution:

明知骨干不希望我对我的模型之间的关系模式，我只是把在网​​址属性到一个函数，包括博客ID：

Knowing that Backbone doesn't expect me to model the relationships between my models, I simply turned the url attribute into a function to include the Blog ID:

class App.Collections.PostsCollection extends Backbone.Collection
  model: App.Models.Post
  url: -> "/blog/" + this.blogId + "/posts"

（请原谅CoffeeScript的。）现在我需要做的 blogId 已知的帖子集合。所以我只是套结它在路由器初始化函数：

(Please excuse the CoffeeScript.) Now I need to make the blogId known to the posts collection. So I'm just tacking it on in the router initialize function:

class App.Routers.PostsRouter extends Backbone.Router
  initialize: (options) ->
    this.posts = new App.Collections.PostsCollection()
    this.posts.blogId = 42  # <----- in reality some meaningful expression ;-)
    this.posts.reset options.positions

这只是不能是正确的？！

That just can't be right?!

请赐教 - 你怎么通常这些模型嵌套集合

Please enlighten me -- how do you usually model these nested collections?

推荐答案

这是解决这个问题的方法之一。另一种方法是创建一个博客的模型。说你给博客模型的帖子（）方法。在这种情况下，可以使用类似的附接blogId的方法，但在博客模型。例如（也在的CoffeeScript，如上）：

This is one way to solve this problem. An alternative is to create a Blog model. Say you give the Blog model a posts() method. In this case you could use a similar method of attaching the blogId, but in the Blog Model. For example (also in Coffeescript, as above):

class App.Models.Blog extends Backbone.Model
  posts: () =>
    @_posts ?= new App.Collections.PostsCollection({blog: this})

，然后在PostsCollection你会：

and then in your PostsCollection you would have:

class App.Collections.PostsCollections extends Backbone.Collection
  url: () => "/blog/#{@options.blog.id}/posts"

让您在路由器更改为：

allowing you to change your router to:

class App.Routers.PostsRouter extends Backbone.Router
  initialize: (options) ->
    # Per your example, an ID of 42 is used below.
    # Ideally, you retrieve the Blog some other way.
    @blog = new App.Models.Blog({id: 42})
    @posts = @blog.posts()

修改您的结构，这样可能会导致额外的模式，但它使你的code更清洁的整体。

Modifying your structure like this might result in an extra model, but it makes your code much cleaner overall.

这篇关于Backbone.js的：建模belongs_to的关系的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！