原生JavaScript实现省市区三级联动下拉框

<!DOCTYPE html>
<html>
<head lang="en">
 <meta charset="UTF-8">
 <title>三级联动测试</title>
 <script src="jquery-2.1.4.min.js"></script>
 <script type="text/javascript">
  //用来获得option元素中selected属性为true的元素的id
  function Get_Selected_Id(place){
   var pro = document.getElementById(place);
   var Selected_Id = pro.options[pro.selectedIndex].id;
   return Selected_Id;   //返回selected属性为true的元素的id
  }
  //改变下一个级联的option元素的内容，即加载市或县
  function Get_Next_Place(This_Place_ID,Action){
   var Selected_Id = Get_Selected_Id(This_Place_ID); //Selected_Id用来记录当前被选中的省或市的ID
   if(Action=='Get_city')       //从而可以在下一个级联中加载相应的市或县
    Add_city(Selected_Id);
   else if(Action=='Get_country')
    Add_country(Selected_Id);
  }
  //用来存储省市区的数据结构
  var Place_dict = {
   "GuangDong":{
       "GuangZhou":["PanYu","HuangPu","TianHe"],
       "QingYuan":["QingCheng","YingDe","LianShan"],
       "FoShan":["NanHai","ShunDe","SanShui"]
       },
   "ShanDong":{
       "JiNan":["LiXia","ShiZhong","TianQiao"],
       "QingDao":["ShiNan","HuangDao","JiaoZhou"]
       },
   "HuNan":{
       "ChangSha":["KaiFu","YuHua","WangCheng"],
       "ChenZhou":["BeiHu","SuXian","YongXian"]
      }
  };
  //加载城市选项
  function Add_city(Province_Selected_Id){
   $("#city").empty();
   $("#city").append("<option>City</option>");
   $("#country").empty();
   $("#country").append("<option>Country</option>");
   //上面的两次清空与两次添加是为了保持级联的一致性
   var province_dict = Place_dict[Province_Selected_Id]; //获得一个省的字典
   for(city in province_dict){  //取得省的字典中的城市
    //添加内容的同时在option标签中添加对应的城市ID
    var text = "<option"+" id='"+city+"'>"+city+"</option>";
    $("#city").append(text);
    console.log(text); //用来观察生成的text数据
   }
  }
  //加载县区选项
  function Add_country(City_Selected_Id){
   $("#country").empty();
   $("#country").append("<option>Country</option>");
   //上面的清空与添加是为了保持级联的一致性
   var Province_Selected_ID = Get_Selected_Id("province");  //获得被选中省的ID，从而方便在字典中加载数据
   var country_list = Place_dict[Province_Selected_ID][City_Selected_Id]; //获得城市列表
   for(index in country_list){
    ////添加内容的同时在option标签中添加对应的县区ID
    var text = "<option"+" id=\'"+country_list[index]+"\'>"+country_list[index]+"</option>";
    $("#country").append(text);
    console.log(text); //用来观察生成的text数据
   }
  }
 
 </script>
</head>
<body>
 <p>您的收货地址：</p>
 <select id="province" onchange="Get_Next_Place('province','Get_city')">
  <option id="Not_data1">Province</option>
  <option id="GuangDong" value="GuangDong">GuangDong</option>
  <option id="ShanDong" value="ShanDong">ShanDong</option>
  <option id="HuNan" value="HuNan">HuNan</option>
 </select>
 <select id="city" onchange="Get_Next_Place('city','Get_country')">
  <option id="Not_data2">City</option>
 </select>
 <select id="country">
  <option id="Not_data3">Country</option>
 </select>
 <br/>
</body>
</html>