<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>二级城市联动</title>
</head>
<body>
<select id="one" onchange="func(this.value)">
<option value="">--请选择--</option>
<option value="0">浙江省</option>
<option value="1">广东省</option>
<option value="2">福建省</option>
</select>
<select id="two">
<option value="">--请选择--</option>
</select>
</body>
<script>
var two = document.getElementById(‘two‘);
city = [];//申明
//定义二级数据
city[0] = [‘杭州市‘];
city[1] = [‘广州市‘];
city[2] = [‘厦门市‘];
function func(m){
two.length = 1;
//遍历生产option选项
for (var i = 0; i < city[m].length; i++) {
//创建一个option 把数据存储在option
var op = new Option(city[m][i],i);
//把带有数据的option 添加到第二个select
two.add(op);
};
}
</script>
</html>
原文：https://www.cnblogs.com/0826sw/p/11798916.html