<body>
<section>
<a>省份</a>
<select id="province">
<option value="0">--请选择--</option>
<option value="1">山东</option> //通过不同的value来区分不同的省份
<option value="2">山西</option>
</select>
<a>城市</a>
<select id="city">
<option>--请选择--</option>
</select>
</section>
</body>
<script>
var arr = new Array();
arr[1] = ["莱芜","济南","东营"];
arr[2] = ["长治","太原","壶关"];
var provinceInput = document.getElementById("province"); //获取省份
var cityInput = document.getElementById("city"); //获取市
provinceInput.onchange = function () {
cityInput.options.length = 1;//当省改变的时候让市的长度为1
for(var i = 0;i < arr[provinceInput.value].length;i++) {
cityInput.add(new Option(arr[provinceInput.value][i])); //向市里面添加对应的数组元素
}
}
</script>
