javascript - 获取结果未定义(Backbone.js)

Question

var ListView = Backbone.View.extend({
    el: $('hello'),
    initialize: function() {
        var stuff = new FieldCollection();
        var output;
        stuff.parse();
        stuff.fetch({
            success: function (collection, response) {
                console.log(response);
                output=response;
                return response;
             }
        });
        this.render(output);
   },
   render:function(output){
        console.log(output);
        $(this.el).append("<button id='add'>hiii</button>");
        $(this.el).append("<button id='removeAll'>Remove all list item</button>");
    }
});

在这里，我试图捕获 output 变量中的响应值...但它出现“未定义”。我有什么错误的想法吗？

Answer 1

fetch 方法是异步的，因此 output 变量在您使用它时尚未被分配。尝试将 render 调用放入成功回调中:

var self = this;
stuff.fetch({
        success: function (collection, response) {
            console.log(response);
            output=response;
            self.render(output);
            return response;
         }
    });