省市联动
<!DOCTYPE HTML>
<HTML>
<HEAD>
<TITLE> New Document </TITLE>
<meta charset="utf-8" />
<script language="JavaScript" type="text/javascript">
//定义了城市的二维数组，里面的顺序跟省份的顺序是相同的。通过selectedIndex获得省份的下标值来得到相应的城市数组
var city=[
["南京","镇江","丹阳","苏州"],
["阜阳","合肥","芜湖","宿州"],
["太原","唐山","邯郸","秦皇岛"],
["威海","日照","潍坊","菏泽"]
];
function getCity(){
//获得省份下拉框的对象
var sltProvince=document.form1.province;
//获得城市下拉框的对象
var sltCity=document.form1.city;
//得到对应省份的城市数组
var provinceCity=city[sltProvince.selectedIndex - 1];
//清空城市下拉框，仅留提示选项
sltCity.length=1;
//将城市数组中的值填充到城市下拉框中
for(var i=0;i<provinceCity.length;i++){
sltCity[i+1]=new Option(provinceCity[i],provinceCity[i]);
}
}
</script>
</HEAD>
<BODY>
<FORM METHOD=POST ACTION="" name="form1">
<SELECT NAME="province" onChange="getCity()">
<OPTION VALUE="0">请选择省份 </OPTION>
<OPTION VALUE="江苏省">江苏省 </OPTION>
<OPTION VALUE="安徽省"> 安徽省</OPTION>
<OPTION VALUE="河北省">河北省 </OPTION>
<OPTION VALUE="山东省"> 山东省</OPTION>
</SELECT>
<SELECT NAME="city">
<OPTION VALUE="0">请选择城市 </OPTION>
</SELECT>
</FORM>
</BODY>
</HTML>
