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));
   }            
}