主干模型.toJSON（）不会呈现所有属性JSON [英] Backbone model .toJSON() doesn't render all attributes to JSON

问题描述

我需要渲染模型对JSON属性，这样我就可以将它们传递到模板。
这里是一个什么渲染（）的视图方法如下：

I need to render a model's attributes to JSON so I can pass them into a template. Here is what a render() function for a view looks like:

render: function() {
  console.log(this.model);
  console.log(this.model.toJSON());
  $(this.el).html(this.template(this.model.toJSON()));
  return this;
},

下面是做的console.log（this.model）后输出的属性：

Here is the attributes output after doing console.log(this.model):

created_at: "2012-04-19"
id: "29"
name: "item"
resource_uri: "/api/v1/item/29/"
updated_at: "2012-04-21"
user: "/api/v1/user/9/"

下面是做的console.log后模型的JSON输出（this.model.toJSON（））：

Here is the model's JSON output after doing console.log(this.model.toJSON()):

id: "29"
__proto__: Object

发生了什么事？

编辑：
这里是实例

Here is the instantiation:

  var goal = new Goal({id: id});
  goal.fetch();
  var goalFullView = new GoalFullView({
    model: goal,
  });

下面是新视图的内容：

  console.log(this.model.attributes);
  console.log(this.model.toJSON());

下面是控制台说什么：

Object
created_at: "2012-04-23"
id: "32"
name: "test"
resource_uri: "/api/v1/goal/32/"
updated_at: "2012-04-23"
user: "/api/v1/user/9/"
__proto__: Object

Object
id: "32"
name: "test"
__proto__: Object

如果在的toJSON应该使属性的克隆，为什么不把它复制正确的名称或者为什么不把它复制了created_at，的updated_at领域？

If the toJSON is supposed to make a clone of the attributes, why doesn't it copy the correct name or why doesn't it copy the created_at, updated_at fields?

编辑2：
下面是模式：

Edit 2: Here is the model:

  var Goal = Backbone.Model.extend({

    // Default attributes for Goal
    defaults: {
      name: "empty goal",
    },

    // Check that the user entered a goal
    validate: function(attrs) {
      if (!attrs.name) {
        return "name is blank";
      }
    },

    // Do HTTP requests on this endpoint
    url: function() {
      if (this.isNew()) {
        return API_URL + "goal/" + this.get("id") + FORMAT_JSON;
      }
      return API_URL + "goal/" + FORMAT_JSON;
      //API_URL + "goal" + FORMAT_JSON, 
    },
  });

编辑3：
我想通了，我需要使用成功回调从取来呈现使用模型视图：

Edit 3: I figured out that I need to use the success callback from fetch to render a view that uses the model:

goal.fetch（{成功：函数（模型）{
    VAR goalFullView =新GoalFullView（{
      型号：目标，
    }）;
  }}）;

goal.fetch({success: function(model) { var goalFullView = new GoalFullView({ model: goal, }); }});

推荐答案

的的toJSON（）方法仅返回模型的属性的浅表副本属性。

The toJSON() method just returns a shallow clone of the model's attributes property.

从注明来源Backbone.js的：

toJSON: function(options) {
  return _.clone(this.attributes);
}

在没有看到您更多的code的，它看起来像你直接设置属性的模型对象上，而不是使用设置函数来设置模型属性。

即。不这样做：

model.name = "item";

做到这一点：

model.set("name", "item");

编辑：

有关您的具体问题，它可能是你叫的toJSON模型已经从服务器加载完成之前。

For your specific issue, it's possible that you called toJSON before the model had finished loading from the server.

例如。这并不总是按预期：

E.g. This won't always work as expected:

var model = new Goal({id: 123});
model.fetch();
console.log(model.toJSON());

但这种意愿：

var model = new Goal({id: 123});
model.fetch({
  success: function() {
    console.log(model.toJSON());
  }
});

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