如何批量分配 Backbone 模型的所有属性？

Question

只要signIn成功，我想更新User 模型。它包括由后端分配的id，以前模型中没有。

MyApp.module("User", function(User, App, Backbone, Marionette, $, _) {

  User.Controller = Backbone.Marionette.Controller.extend({

    initialize: function() {
      this.model = new MyApp.User.Model();
    },

    signIn: function(credentials) {
      var signInData = { user: credentials };
      var self = this;

      App.session.signIn(signInData, {
        success: function(model, response, options) {
          self.updateUserModel(model);
        },
        error: function(model, xhr, options) {}
      });
    },

    updateUserModel: function(model) {
      // TODO Update all attributes, including new onces e.g. id.
    }

  });
});

如何一次更新所有属性？我知道我可以手动 set 每个属性，但这似乎是错误的，因为属性列表可能会随着时间而改变。
一般来说，我希望User 模型中有这样的update(model) 方法。

---

当我按照 nikoshr 和 john-4d5 的建议使用 Backbone 的 model.set() 方法时...

    signIn: function(credentials) {
      var signInData = { user: credentials };
      var self = this;

      App.session.signIn(signInData, {
        success: function(model, response, options) {
          self.model.set(model);
        },
        error: function(model, xhr, options) {}
      });
    },

...id 属性已复制到 this.model，但缺少其他属性，例如 name。

success 回调中返回的模型如下所示：

_changing: false
_pending: false
_previousAttributes: Object
attributes: Object
    bind: function (name, callback, context) {
    close: function (){
    constructor: function (){ return parent.apply(this, arguments); }
    created_at: "2013-07-22T19:03:24Z"
    email: "user@example.com"
    id: 3
    initialize: function () {
    listenTo: function (obj, name, callback) {
    listenToOnce: function (obj, name, callback) {
    logout: function () {
    model: child
    name: "Some User"
    off: function (name, callback, context) {
    on: function (name, callback, context) {
    once: function (name, callback, context) {
    options: Object
    signIn: function (credentials) {
    signUp: function (credentials) {
    stopListening: function (obj, name, callback) {
    trigger: function (name) {
    triggerMethod: function (event) {
    unbind: function (name, callback, context) {
    updated_at: "2013-08-05T13:20:43Z"
    user: Object
    __proto__: Object
    changed: Object
cid: "c3"
id: 3
__proto__: Surrogate

Answer 1

• 您正在Backbone.Model 附近移动，
• Model.set 接受属性哈希，
• 您可以将Backbone.Model 转换为带有Model.toJSON 的属性哈希值

你可以把你的回调写成

success: function(model, response, options) {
    self.model.set(model.toJSON());
}

Answer 2

您可以简单地使用set，将另一个模型的attributes 属性值（具有所有属性值的对象）作为参数。

self.model.set(model.attributes);

Answer 3

您可以像@nikoshr 所说的那样使用this.model.set(model)。遍历属性并设置每个属性将做与 model.set 已经做的事情相同的事情。参考主干的model.set函数：

// Set a hash of model attributes on the object, firing `"change"`. This is
// the core primitive operation of a model, updating the data and notifying
// anyone who needs to know about the change in state. The heart of the beast.
set: function(key, val, options) {
  var attr, attrs, unset, changes, silent, changing, prev, current;
  if (key == null) return this;

  // Handle both `"key", value` and `{key: value}` -style arguments.
  if (typeof key === 'object') {
    attrs = key;
    options = val;
  } else {
    (attrs = {})[key] = val;
  }

  [...]

  // For each `set` attribute, update or delete the current value.
  for (attr in attrs) {
    val = attrs[attr];
    if (!_.isEqual(current[attr], val)) changes.push(attr);
    if (!_.isEqual(prev[attr], val)) {
      this.changed[attr] = val;
    } else {
      delete this.changed[attr];
    }
    unset ? delete current[attr] : current[attr] = val;
  }
 [...]
}

另一种选择是实例化一个新模型：

this.model = new MyApp.User.Model(model);