javascript - Collection.get 在 backbone.js 中返回未定义

Question

我对 collection.get 和 model.get 返回未定义有疑问。

这是我的初始化代码

initialize: function () {
    this.collection = new productsCollection();
    this.model = new productModel();
}

这是我的渲染代码

this.collection.fetch({
    success: function (product) {
        console.log(product);
        $(that.el).html(_.template(productListTemplate, { products: product.models, _: _ }));
    }
});

我的产品列表显示正常。当我点击每个产品时，我会看到一个可以更改名称的弹出窗口

我想在模型中获取设置的新名称并触发保存

但是我无法得到产品的型号这里是代码

$("#productName").val($(e.currentTarget).html());

var ID = $(e.currentTarget).data("id");
var item = this.collection.get(ID);

console.log("start..........");
console.log(item);
console.log(ID)
//            console.log(this.collection);
console.log(this.model.get(item));
console.log("end..........");

$('.modal').modal('toggle');

我能够在控制台中获得正确的 id，但不能获得集合和模型

谁能帮忙提前谢谢

更新这是完整的 View 代码

function ($, _, Backbone, popupModal, productTab, productsCollection, productListTemplate, productModel) {
    var productListView = Backbone.View.extend({
        el: $("#page"),
        initialize: function () {
            this.collection = new productsCollection();
            this.model = new productModel();
            this.model.bind('change', this.loadResults, this);
        },
        render: function () {
            this.loadResults();
        },
        loadResults: function () {
            var that = this;
            this.collection.fetch({
                success: function (product) {
                    console.log(product);
                    $(that.el).html(_.template(productListTemplate, { products: product.models, _: _ }));
                }
            });
            var modalWindow = $(".modal").modal({
                show: false,
                backdrop: true,
                closeOnEscape: true
            });
            $('#createProduct').click(function (e) {
                this.modalWindow.modal('show');
            });
        },
        // This will simply listen for scroll events on the current el
        events: {
            "click #saveProduct": "saveProduct",
            "click .productTabs": "productTabs",
            "click .productDetails": "productDetails"
        },
        saveProduct: function () {
            this.model.set({
                Name: $('#productName').val()
            });
            this.model.save({ id: this.model.get('id') },
         {
             success: function (model, response) {
                 //                 console.log("success");
             },
             error: function (model, response) {
                 //                 console.log(response);
                 var errorMsg = JSON.parse(response.responseText);
                 $(".errorMessage").html('<div class="alert alert-error">' + errorMsg.Error + '</div>');
             }
         });
        },
        productTabs: function (e) {
            e.preventDefault();
            $(this).tab('show');
        },
        productDetails: function (e) {
            e.preventDefault();
            $("#productName").val($(e.currentTarget).html());
            var ID = $(e.currentTarget).data("id");
            var item = this.collection.get(ID);
            console.log("start..........");
            console.log(item);
            console.log(ID)
            //            console.log(this.collection);
            console.log(this.collection.models.get(item));
            console.log("end..........");
            $('.modal').modal('toggle');
        }
    });
    return new productListView;
});

更新回复

this.collection

b.hasOwnProperty.e
_byCid: Object
_byId: Object
_onModelEvent: function () { [native code] }
_removeReference: function () { [native code] }
length: 2
models: Array[2]
0: b.hasOwnProperty.e
1: b.hasOwnProperty.e
length: 2
__proto__: Array[0]
__proto__: s​

它有 2 个型号，我的列表也有 2 个产品

this.model

_callbacks: Object
_changed: false
_changing: false
_escapedAttributes: Object
_previousAttributes: Object
attributes: Object
ID: ""
Name: ""
hRef: ""
__proto__: Object
cid: "c2"
__proto__: s

属性为空

这让我关注

cid: "view1"
collection: b.hasOwnProperty.e
_byCid: Object
_byId: Object
_onModelEvent: function () { [native code] }
_removeReference: function () { [native code] }
length: 2
models: Array[2]
__proto__: s
model: b.hasOwnProperty.e
_callbacks: Object
_changed: false
_changing: false
_escapedAttributes: Object
_previousAttributes: Object
attributes: Object
cid: "c2"
__proto__: s
options: Object
__proto__: s

更新 这是我扩展收藏时看到的内容

b.hasOwnProperty.e
_byCid: Object
_byId: Object
_onModelEvent: function () { [native code] }
_removeReference: function () { [native code] }
length: 2
models: Array[2]
0: b.hasOwnProperty.e
_callbacks: Object
_changed: false
_changing: false
_escapedAttributes: Object
_previousAttributes: Object
attributes: Object
ID: "7e0c94fc-7c16-45c9-84a9-a0690103b946"
Name: "dsa"
hRef: "Product/dsa"
__proto__: Object
cid: "c3"
collection: b.hasOwnProperty.e
__proto__: s
1: b.hasOwnProperty.e
length: 2
__proto__: Array[0]
__proto__: s

Answer 1

问题是您必须将所有将由 DOM 事件调用的函数绑定(bind)到您的 View 实例:

因此将这一行添加到您的initialize 方法中:

_.bindAll(this, "saveProduct", "productTabs", "productDetails")

否则函数中的 this 将是全局 window 对象，而不是 View 的实例。