最近在网上找了一效果非常不错的Js级联菜单，可以无限制的增加级联。
所要引用的JS文件：点击此处下载
<meta http-equiv="Content-Type" content="text/html; charset=gb2312">
<title>javascript无限级联动菜单</title>
<script src="prototype.js"></script>
<script src="linkage.js"></script>
</head>
<body>
<!-- 加载数据源 -->
<xml id="dataSrc2" style="height:0px; width:0px; visibility:hidden;">
<TreeNodes>
<TreeNode Value="玻璃">
<TreeNode Value="建筑玻璃">
<TreeNode Value="玻璃幕墙">
<TreeNode Value="中空玻璃"></TreeNode>
<TreeNode Value="真空玻璃"></TreeNode>
<TreeNode Value="夹胶玻璃"></TreeNode>
</TreeNode>
<TreeNode Value="玻璃门窗">
<TreeNode Value="特种玻璃">
<TreeNode Value="防火玻璃"></TreeNode>
<TreeNode Value="防爆玻璃"></TreeNode>
<TreeNode Value="防弹玻璃"></TreeNode>
</TreeNode>
<TreeNode Value="平板玻璃"></TreeNode>
<TreeNode Value="有机玻璃"></TreeNode>
<TreeNode Value="玻璃深加工制品">
<TreeNode Value="镀膜玻璃"></TreeNode>
<TreeNode Value="中空玻璃"></TreeNode>
<TreeNode Value="真空玻璃"></TreeNode>
</TreeNode>
</TreeNode>
</TreeNode>
<TreeNode Value="汽车玻璃">
</TreeNode>
<TreeNode Value="液晶玻璃">
</TreeNode>
<TreeNode Value="工程玻璃">
<TreeNode Value="钢化玻璃"></TreeNode>
<TreeNode Value="半钢化玻璃"></TreeNode>
<TreeNode Value="中空玻璃"></TreeNode>
<TreeNode Value="夹层玻璃"></TreeNode>
</TreeNode>
</TreeNode>
<TreeNode Value="幕墙">
<TreeNode Value="点支式"></TreeNode>
<TreeNode Value="平头点支式">
<TreeNode Value="肋驳接点式"></TreeNode>
<TreeNode Value="钢结构点式"></TreeNode>
<TreeNode Value="钢拉杆点式"></TreeNode>
<TreeNode Value="双层索点式"></TreeNode>
<TreeNode Value="单层索点式"></TreeNode>
</TreeNode>
<TreeNode Value="凸头点支式"></TreeNode>
<TreeNode Value="挂钩式"></TreeNode>
<TreeNode Value="框架式">
<TreeNode Value="全隐式">
<TreeNode Value="压块式"></TreeNode>
<TreeNode Value="挂接式"></TreeNode>
</TreeNode>
<TreeNode Value="半隐式"></TreeNode>
<TreeNode Value="明框式">
<TreeNode Value="压块式"></TreeNode>
<TreeNode Value="挂接式"></TreeNode>
</TreeNode>
</TreeNode>
</TreeNode>
<TreeNode Value="工业型材">
<TreeNode Value="肋驳接点式">
<TreeNode Value="工业大断面"></TreeNode>
<TreeNode Value="电力铝排"></TreeNode>
<TreeNode Value="电子散热器"></TreeNode>
</TreeNode>
<TreeNode Value="门窗型材">
<TreeNode Value="嵌条式保温门窗">
<TreeNode Value="内外平开窗"></TreeNode>
<TreeNode Value="内外平开门窗"></TreeNode>
<TreeNode Value="内开窗"></TreeNode>
<TreeNode Value="推拉门窗"></TreeNode>
<TreeNode Value="内开门窗"></TreeNode>
</TreeNode>
</TreeNode>
<TreeNode Value="幕墙型材">
<TreeNode Value="全隐幕墙"></TreeNode>
<TreeNode Value="半隐幕墙"></TreeNode>
<TreeNode Value="明框幕墙"></TreeNode>
<TreeNode Value="小单元式幕墙"></TreeNode>
</TreeNode>
<TreeNode Value="铝型材">
<TreeNode Value="大厦"></TreeNode>
<TreeNode Value="建筑"></TreeNode>
<TreeNode Value="工业"></TreeNode>
<TreeNode Value="汽车行业"></TreeNode>
<TreeNode Value="其它"></TreeNode>
</TreeNode>
</TreeNode>
<TreeNode Value="设备">
<TreeNode Value="玻璃深加工">
<TreeNode Value="玻璃磨边"></TreeNode>
<TreeNode Value="玻璃钻空"></TreeNode>
</TreeNode>
<TreeNode Value="铝合金门窗">
<TreeNode Value="锯切类"></TreeNode>
<TreeNode Value="组角类"></TreeNode>
<TreeNode Value="铣削类"></TreeNode>
<TreeNode Value="压力类"></TreeNode>
<TreeNode Value="辅助"></TreeNode>
</TreeNode>
<TreeNode Value="塑料门窗">
<TreeNode Value="焊接类"></TreeNode>
<TreeNode Value="锯切类"></TreeNode>
<TreeNode Value="铣削类"></TreeNode>
<TreeNode Value="清角类"></TreeNode>
<TreeNode Value="辅助"></TreeNode>
</TreeNode>
<TreeNode Value="实验设备"></TreeNode>
<TreeNode Value="中空玻璃">
<TreeNode Value="自动生产线"></TreeNode>
<TreeNode Value="清洗类"></TreeNode>
<TreeNode Value="辊压类"></TreeNode>
<TreeNode Value="合片类"></TreeNode>
<TreeNode Value="涂胶类"></TreeNode>
<TreeNode Value="辅助"></TreeNode>
</TreeNode>
</TreeNode>
<TreeNode Value="板材">
</TreeNode>
<TreeNode Value="配件">
</TreeNode>
<TreeNode Value="门窗">
</TreeNode>
<TreeNode Value="五金">
</TreeNode>
<TreeNode Value="软件">
</TreeNode>
<TreeNode Value="其他">
</TreeNode>
</TreeNodes>
</xml>
<select name="cplx" id="cplx" USEDATA="dataSrc2" SUBCLASS="1">
</select>
<select name="yt" id="yt" USEDATA="dataSrc2" SUBCLASS="2">
</select>
<select name="gl" id="gl" USEDATA="dataSrc2" SUBCLASS="3">
</select>
<select name="ld" id="ld" USEDATA="dataSrc2" SUBCLASS="4">
</select>
<select name="zf" id="zf" USEDATA="dataSrc2" SUBCLASS="5">
</select>
</body>
</html>
<script language="javascript">
var linkage2 = new Linkage("dataSrc2");
linkage2.init();
//初始化数据
linkage2.initLinkage("dataSrc2","玻璃",1);
</script>