基于JSON的级联列表实现

html代码：

 <select id="provice" onChange="setCity()">
     <option value="">--请选择省份--</option>
 </select>

 <select id="city">
     <option value="">--请选择城市--</option>
 </select>

JS代码：

 var provideJson = {"1":"河北省","2":"直辖市"};
 var cityJson = {"1":{"01":"石家庄市","02":"衡水市","03":"邯郸市","04":"邢台市","05":"正定市"},"2":{"001":"北京市","002":"上海市","003":"天津市","004":"重庆市"}};
 window.onload=function()
 {
     var proSel = document.getElementById("provice");
     for(tmp in provideJson)
     {
          proSel.add(new Option(provideJson[tmp],tmp));
     }
 }
 function setCity()
 {
    var proVal = document.getElementById("provice").value;
    var city = document.getElementById("city");
    city.options.length=1;
    if(proVal == "") return;
    for(temp in cityJson[proVal])
    {
         console.info(cityJson[proVal][temp]);
         city.add(new Option(cityJson[proVal][temp],temp));
    }
 }