Question

我正在开发一个在主视图模型中打包多个viewModel的UI。您可以看到以下结构：

function commonVM() {
   self = this;

   //initialize observable variables
   self.start_searching_visible = ko.observable(true); //start searching panel visible    
};

function searchCriteriaVM() {
   self = this;

   self.window_location = ko.observable("#/");
   self.company_search_criteria_visible = ko.observable(true);    
}

appViewModel = function () { 
   self = this;

   //False if the view has already been initialized
   isInitialized = false;
   self.commonViewModel = new commonVM();
   self.searchCriteriaViewModel = new searchCriteriaVM();     
   self.commonViewModel.start_searching_visible();     
}

var test = new appViewModel();
ko.applyBindings(test);

我收到了searchCriteriaViewModel未定义错误。我为什么要这个？为什么我不能访问这个变量，虽然我已经在上面的陈述中初始化了？

Answer 1

在变量decalre时使用var。当您错过var关键字时，变量将被声明为全局变量。在您的情况下self首先引用appViewModel，但是当您创建commonVM时，self变量会被赋予不同的值，然后它在全局中具有不同的含义。

但是你有很多其他错误 - 没有将start_searching_visible附加到此/ self，并且无法从实例访问它，从错误的视图模型调用start_searching_visible等。

function commonVM() {
    var self = this;

    //initialize observable variables
    self.start_searching_visible = ko.observable(true); //start searching panel visible    
};

function searchCriteriaVM() {
    var self = this;

    self.window_location = ko.observable("#/");
    self.company_search_criteria_visible = ko.observable(true);
}

appViewModel = function() {
    var self = this;

    //False if the view has already been initialized
    self.isInitialized = false;
    self.commonViewModel = new commonVM();
    self.searchCriteriaViewModel = new searchCriteriaVM();
    self.commonViewModel.start_searching_visible();
    // self.searchCriteriaViewModel.start_searching_visible();     
}

var test = new appViewModel();
ko.applyBindings(test);

我建议完成一些JavaScript（OOP）课程/教程。

淘汰多个视图模型 - 未定义

1 个答案: