JavaScript 省市级联效果

 1 <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
 2 <html xmlns="http://www.w3.org/1999/xhtml">
 3 <head>
 4     <title>省市级联效果</title>
 5 
 6     <script type="text/javascript">
 7         function show() {
 8             var citys = new Array();
 9             citys["湖北省"] = ["襄樊市", "武汉市", "随州市", "荆门市", "黄石市", "恩施市", "咸宁市", "仙桃市", "十堰市", "孝感市", "利川市"];
10             citys["湖南省"] = ["长沙市", "吉首市", "湘潭市", "益阳市", "津市市", "洪江市", "怀化市", "冷水江市", "衡阳市", "郴州市", "永州市", "邵阳市", "岳阳市"];
11             citys["广东省"] = ["广州市", "深圳市", "佛山市", "汕头市", "珠海市", "韶关市", "江门市", "湛江市", "惠州市", "中山市", "东莞市"];
12             citys["北京市"] = ["朝阳区", "丰台区", "崇文区", "宣武区", "海淀区", "顺义区", "平谷区", "怀柔区", "房山区", "东城区", "西城区"];
13 
14             document.getElementById("shi").options.length = 1;
15             var sheng = document.getElementById("sheng").value;
16             var newCity;
17             if (sheng != "-=请选择=-") {
18                 for (var i = 0; i < citys[sheng].length; i++) {
19                     newCity = new Option(citys[sheng][i], citys[sheng][i]);
20                     document.getElementById("shi").options.add(newCity);
21                 }
22             }
23         }
24     
25     </script>
26 
27 </head>
28 <body>
29     <div>
30         <select id="sheng" onchange="show()">
31             <option value="-=请选择=-">-=请选择=-</option>
32             <option value="湖北省">湖北省</option>
33             <option value="湖南省">湖南省</option>
34             <option value="广东省">广东省</option>
35             <option value="北京市">北京市</option>
36         </select>
37         <select id="shi">
38             <option>-=请选择=-</option>
39         </select>
40     </div>
41 </body>
42 </html>