三级联动效果
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
<script type="text/javascript">
var cityList = new Array();
var quList = new Array();
cityList['北京'] = ['北京'];
cityList['浙江'] = ['杭州市', '温州市', '金华市', '临安市'];
cityList['陕西'] = ['西安', '宝鸡', '咸阳'];
cityList['甘肃'] = ['兰州市', '武威市', '酒泉市', '张掖市'];
quList['北京'] = ['1区', '2区', '3区', '4区'];
quList['杭州市'] = ['5区', '6区', '7区', '8区'];
quList['温州市'] = ['9区', '10区', '11区', '12区'];
quList['西安'] = ['13区', '14区', '15区', '16区'];
quList['宝鸡'] = ['17区', '18区', '19区', '20区'];
quList['兰州市'] = ['21区', '22区', '23区', '24区'];
window.onload = allData;
function allData() {
var shengfen = document.getElementById('shengfen');
for(var sf in cityList) {
shengfen.add(new Option(sf, sf));
}
}
function changeCity() {
var chengshi = document.getElementById('chengshi');
var sheng = document.getElementById('shengfen').value;
chengshi.options.length = 1;
for(var cs in cityList[sheng]) {
chengshi.add(new Option(cityList[sheng][cs], cityList[sheng][cs]));
}
}
function changequ() {
var shiqu = document.getElementById('shiqu');
var cheng = document.getElementById('chengshi').value;
shiqu.options.length = 1;
for(var sh in quList[cheng]) {
shiqu.add(new Option(quList[cheng][sh], quList[cheng][sh]));
}
}
</script>
</head>
<body>
<br />
<select id="shengfen" style="width:100px" onchange="changeCity()">
<option>--选择省份--</option>
</select>
<select id="chengshi" style="width:100px" onchange="changequ()">
<option>--选择城市--</option>
</select>
<select id="shiqu" style="width:100px">
<option>--选择区县--</option>
</select>
</body>
</html>
参考链接：http://www.cnblogs.com/zjfree/archive/2011/11/30/2269342.html
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title></title>
</head>
<body>
省：
<select style="width: 100px;" id="pre" onchange="chg(this);">
<option value="-1">请选择</option>
</select>
市：
<select style="width: 100px;" id="city" onchange="chg2(this);"></select>
区：
<select style="width: 100px;" id="area"></select>
</body>
<script>
//声明省
var pres = ["北京", "上海", "山东"]; //直接声明Array
//声明市
var cities = [
["东城", "昌平", "海淀"],
["浦东", "高区"],
["济南", "青岛"]
];
var areas = [
[
["东城1", "东城2", "东城3"],
["昌平1", "昌平2", "昌平3"],
["海淀1", "海淀2", "海淀3"]
],
[
["浦东1", "浦东2", "浦东3"],
["高区1", "高区2", "高区3"]
],
[
["济南1", "济南2"],
["青岛1", "青岛2"]
]
]
//设置一个省的公共下标
var pIndex = -1;
var preEle = document.getElementById("pre");
var cityEle = document.getElementById("city");
var areaEle = document.getElementById("area");
//先设置省的值
for(var i = 0; i < pres.length; i++) {
//声明option.<option value="i">pres[i]</option>
var op = new Option(pres[i], i);
//添加
preEle.options.add(op);
}
function chg(obj) {
if(obj.value == -1) {
cityEle.options.length = 0;
areaEle.options.length = 0;
return true;
}
//获取值
var val = obj.value;
pIndex = obj.value;
//获取ctiry
var cs = cities[val];
//获取默认区
var as = areas[val][0];
//先清空市
cityEle.options.length = 0;
areaEle.options.length = 0;
for(var i = 0; i < cs.length; i++) {
var op = new Option(cs[i], i);
cityEle.options.add(op);
}
for(var i = 0; i < as.length; i++) {
var op = new Option(as[i], i);
areaEle.options.add(op);
}
}
function chg2(obj) {
var val = obj.selectedIndex;
var as = areas[pIndex][val];
areaEle.options.length = 0;
for(var i = 0; i < as.length; i++) {
var op = new Option(as[i], i);
areaEle.options.add(op);
}
}
</script>
</html>
