调用主干集合的获取函数时"Undefined is not a function"错误

Question

我在调用fetch函数时会遇到错误。

Undefined is not a function Error in Backbone js 

var models = Backbone.Model.extend({
  userId: function() {
    return this.get('userId');
  },
  id: function() {
    return this.get('id');
  },
  body: function() {
    return this.get('body');
  }
});
//Collections
var todolistStore = Backbone.Collection.extend({
  url: function() {
    return 'https://jsonplaceholder.typicode.com/posts'
  },
  model: models,
  parse: function(response) {
    return response;
  }
});
todolistStore.fetch();

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<script src="https://ajax.cdnjs.com/ajax/libs/underscore.js/1.1.4/underscore-min.js" type="text/javascript"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/backbone.js/0.9.2/backbone-min.js" type="text/javascript"></script>

Answer 1

有几个问题。我是在@chrisg的答案中建立的。

1. 您需要实例化集合。这是我的代码：

   var Model = Backbone.Model.extend({
       userId: function() {
           return this.get('userId');
       },
       id: function() {
           return this.get('id');
       },
       body: function() {
           return this.get('body');
       }
   });
   //Collections
   var TodoListStore = Backbone.Collection.extend({
       url: function() {
           return 'https://jsonplaceholder.typicode.com/posts'
       },
       model: Model,
       parse: function(response) {
           return response;
       }
   });
   var todolistStore = new TodoListStore();
   todolistStore.fetch();
   

2. 我更新了下划线和骨干的版本

   https://cdnjs.cloudflare.com/ajax/libs/underscore.js/1.8.3/underscore-min.jshttps://cdnjs.cloudflare.com/ajax/libs/backbone.js/1.3.3/backbone-min.js