实现 鼠标移上去出现多菜单
<HTML> <HEAD> <title>WebForm5</title> <style>/* Root = Horizontal, Secondary = Vertical */ul#navmenu-h { margin: 0; border: 0 none; padding: 0; width: 500px; /*For KHTML*/ list-style: none; height: 24px;}ul#navmenu-h li { margin: 0; border: 0 none; padding: 0; float: left; /*For Gecko*/ display: inline; list-style: none; position: relative; height: 24px;}ul#navmenu-h ul { margin: 0; border: 0 none; padding: 0; width: 160px; list-style: none; display: none; position: absolute; top: 24px; left: 0;}ul#navmenu-h ul:after /*From IE 7 lack of compliance*/{ clear: both; display: block; font: 1px/0px serif; content: "."; height: 0; visibility: hidden;}ul#navmenu-h ul li { width: 160px; float: left; /*For IE 7 lack of compliance*/ display: block !important; display: inline; /*For IE*/}/* Root Menu */ul#navmenu-h a { border: 1px solid #FFF; border-right-color: #CCC; border-bottom-color: #CCC; padding: 0 6px; float: none !important; /*For Opera*/ float: left; /*For IE*/ display: block; background: #EEE; color: #666; font: bold 10px/22px Verdana, Arial, Helvetica, sans-serif; text-decoration: none; height: auto !important; height: 1%; /*For IE*/}/* Root Menu Hover Persistence */ul#navmenu-h a:hover,ul#navmenu-h li:hover a,ul#navmenu-h li.iehover a { background: #CCC; color: #FFF;}/* 2nd Menu */ul#navmenu-h li:hover li a,ul#navmenu-h li.iehover li a { float: left; background: #EEE; color: green;}/* 2nd Menu Hover Persistence */ul#navmenu-h li:hover li a:hover,ul#navmenu-h li:hover li:hover a,ul#navmenu-h li.iehover li a:hover,ul#navmenu-h li.iehover li.iehover a { background: #CCC; color: red;}/* 3rd Menu */ul#navmenu-h li:hover li:hover li a,ul#navmenu-h li.iehover li.iehover li a { background: #EEE; color: #666;}/* 3rd Menu Hover Persistence */ul#navmenu-h li:hover li:hover li a:hover,ul#navmenu-h li:hover li:hover li:hover a,ul#navmenu-h li.iehover li.iehover li a:hover,ul#navmenu-h li.iehover li.iehover li.iehover a { background: #CCC; color: #FFF;}/* 4th Menu */ul#navmenu-h li:hover li:hover li:hover li a,ul#navmenu-h li.iehover li.iehover li.iehover li a { background: #EEE; color: #666;}/* 4th Menu Hover */ul#navmenu-h li:hover li:hover li:hover li a:hover,ul#navmenu-h li.iehover li.iehover li.iehover li a:hover { background: #CCC; color: #FFF;}ul#navmenu-h ul ul,ul#navmenu-h ul ul ul { display: none; position: absolute; top: 0; left: 160px;}/* Do Not Move - Must Come Before display:block for Gecko */ul#navmenu-h li:hover ul ul,ul#navmenu-h li:hover ul ul ul,ul#navmenu-h li.iehover ul ul,ul#navmenu-h li.iehover ul ul ul { display: none;}ul#navmenu-h li:hover ul,ul#navmenu-h ul li:hover ul,ul#navmenu-h ul ul li:hover ul,ul#navmenu-h li.iehover ul,ul#navmenu-h ul li.iehover ul,ul#navmenu-h ul ul li.iehover ul { display: block;}</style><script language="javascript">navHover = function() { var lis = document.getElementById("navmenu-h").getElementsByTagName("LI"); for (var i=0; i<lis.length; i++) { lis[i].onmouseover=function() { this.className+=" iehover"; } lis[i].onmouseout=function() { this.className=this.className.replace(new RegExp(" iehover\\b"),""); } }}if (window.attachEvent) window.attachEvent("onload", navHover);</script> </HEAD> <body><ul id="navmenu-h"> <li><a href="#">Root nav item1</a><ul><li><a href="#">Sub nav item1</a></li><li><a href="#">Sub nav item1-2</a></li></ul> </li><li><a href="#">Root nav item2</a><ul><li><a href="#">Sub nav item2</a></li><li><a href="#">Sub nav item2-2</a></li></ul> </li> <li><a href="#">Root nav item3</a><ul><li><a href="#">Sub nav item3</a></li><li><a href="#">Sub nav item3-2</a></li></ul> </li></ul></body></html>