knockoutjs 的变量的作用域是怎么定义的？

悬赏园豆：5 [已解决问题] 解决于 2013-09-16 15:52

 1 function  viewModel(){
 2     var self = this;
 3     self.Areas=[new Area(1,"龙城"), new Area(2,"横岗"), new Area(3,"平湖"), new Area(4,"布吉"), new Area(5,"坂田"), new Area(6,"南湾"), new Area(7,"龙岗")];
 4     self.RestaurantTypes=[new RestaurantType(1,"粤菜"),new RestaurantType(2,"客家菜"),new RestaurantType(3,"川菜")] ;
 5     self.AreaName=ko.observable("NanJing");
 6     self.showSelectedValue = ko.observable(true);
 7     self.click_area = function(msg){
 8         self.AreaName=("BeiJing");
 9         self.showSelectedValue = false;
10         alert("AreaName:"+self.AreaName);
11         alert("showSelectedValue:"+self.showSelectedValue);
12         
13     }
14     this.click_type = function(){
15         alert("AreaName:"+self.AreaName);
16         alert("showSelectedValue:"+self.showSelectedValue);
17     }
18 
19 };