knockout.js - Knockoutjs - 使用映射插件订阅

Question

我正在使用 knockout 映射插件，以前我会像这样设置订阅

self.selectedProduct.subscribe(function (name) {

}
  but I'm unsure of how to do this in this format below. The message I get is

“丢失:在属性 ID 之后”

 var viewModel = {

    products: ko.mapping.fromJS([]),
    productOptions: ko.mapping.fromJS([]),
    productOptions.subscribe = function (name) {
        alert('somthing change');
    },
    loadInitialData: function () {
        ko.mapping.fromJS(serverData, viewModel.productOptions);
    }
  }

Answer 1

如果您将 View 模型定义为对象字面量，则不能像内联那样进行函数调用。您必须在创建 View 模型或以不同方式创建 View 模型后执行此操作。

如果你后来做了，那么它看起来像:

  var viewModel = {
    products: ko.mapping.fromJS([]),
    productOptions: ko.mapping.fromJS([]),
    loadInitialData: function () {
        ko.mapping.fromJS(serverData, viewModel.productOptions);
    }
  };

   viewModel.productOptions.subscribe = function (name) {
        alert('somthing change');
   };

如果您使用构造函数创建 View 模型，则它看起来像:

var ViewModel = function() {
    this.products = ko.mapping.fromJS([]);
    this.productOptions = ko.mapping.fromJS([]);
    this.productOptions.subscribe = function(name) {
         alert("something change");
    };

    this.loadInitialData = function() {
        ko.mapping.fromJS(serverData, this.productOptions);
    };
};


var viewModel = new ViewModel();