Ajax级联上拉框菜单 _Ajax

Ajax级联下拉框菜单
<script>
	//构造2个数组
	var detail_show = new Array();
	var detail_value = new Array();
	detail_show[0] = new Array();
	detail_value[0] = new Array();
	detail_show[0][0] = '上海';
	detail_value[0][0] = '0101';
	detail_show[0][1] = '北京';
	detail_value[0][1] = '0102';
	detail_show[0][2] = '广州';
	detail_value[0][2] = '0103';
	detail_show[1] = new Array();
	detail_value[1] = new Array();
	detail_show[1][0] = '纽约';
	detail_value[1][0] = '0201';
	detail_show[1][1] = '华盛顿';
	detail_value[1][1] = '0202';
	detail_show[1][2] = '加州';
	detail_value[1][2] = '0203';
	detail_show[2] = new Array();
	detail_value[2] = new Array();
	detail_show[2][0] = '伦敦';
	detail_value[2][0] = '0301';
	detail_show[2][1] = '利物浦';
	detail_value[2][1] = '0302';
	detail_show[2][2] = '伯明翰';
	detail_value[2][2] = '0303';

	function change(target) {
		//获取级联的下拉列表
		var deselect = document.getElementById("deselect");
		//清空第二个下拉列表的选项
		deselect.innerHTML = null;
		var m = target.selectedIndex;
		if (m >= 0) {
			for (i = 0; i < detail_show[m].length; i++) {
				//循环构造很多option,然后放在指定的option中
				//new Option(show,value)可以构造一个一个的option
				deselect.options[i] = new Option(detail_show[m][i],
						detail_value[m][i]);
			}
			//设置默认选中第一个列表项
			deselect.options[0].selected = true;
		}
	}
</script>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" 
	"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
	<head>
		<title>级联菜单</title>
		<meta name="author" content="Yeeku.H.Lee" />
		<meta http-equiv="Content-Type" content="text/html; charset=GBK" />
		<link href="css/css.css" rel="stylesheet" type="text/css" />
	</head>
	<body>
		<div align="center">
			<h2>
				级联菜单
			</h2>
			<form id="flyform">
				<select name="caselect" id="caselect" style="width: 80"
					onchange="change(this)";>
					<option value="01">
						中国
					</option>
					<option value="02">
						美国
					</option>
					<option value="03">
						英国
					</option>
				</select>
				<select name="deselect" id="deselect" style="width: 150">
				</select>
			</form>
		</div>
	</body>
</html>