本文实例讲述了JS+CSS实现大气清新的滑动菜单效果代码。分享给大家供大家参考，具体如下：
这是一款比较大气清新的滑动导航菜单，CSS和JavaScript配合完成，鼠标放到一级菜单上，会滑出二级的菜单，兼容性也不错，适合大多数网站使用，用到两张背景图片，请拷贝图片地址下载图片。
运行效果截图如下：
在线演示地址如下：
http://demo.jb51.net/js/2015/js-css-dqqx-scroll-menu-demo/
具体代码如下：
<!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><meta http-equiv="Content-Type" content="text/html; charset=gb2312" /><title>滑动导航菜单</title><style>body {margin:25px; font:12px Verdana, Arial, Helvetica}* {padding:0; margin:0}.dropdown {float:left; padding-right:5px}.dropdown dt {width:188px; border:2px solid #9ac1c9; padding:8px; font-weight:bold; cursor:pointer; background:url(images/header.gif)}.dropdown dt:hover {background:url(images/header_over.gif)}.dropdown dd {position:absolute; overflow:hidden; width:208px; display:none; background:#fff; z-index:200; opacity:0}.dropdown ul {width:204px; border:2px solid #9ac1c9; list-style:none; border-top:none}.dropdown li {display:inline}.dropdown a, .dropdown a:active, .dropdown a:visited {display:block; padding:5px; color:#333; text-decoration:none; background:#eaf0f2; width:194px}.dropdown a:hover {background:#d9e1e4; color:#000}.dropdown .underline {border-bottom:1px solid #b9d6dc}</style><script type="text/javascript">var DDSPEED = 10;var DDTIMER = 15;function ddMenu(id,d){ var h = document.getElementById(id + '-ddheader'); var c = document.getElementById(id + '-ddcontent'); clearInterval(c.timer); if(d == 1){ clearTimeout(h.timer); if(c.maxh && c.maxh <= c.offsetHeight){return} else if(!c.maxh){ c.style.display = 'block'; c.style.height = 'auto'; c.maxh = c.offsetHeight; c.style.height = '0px'; } c.timer = setInterval(function(){ddSlide(c,1)},DDTIMER); }else{ h.timer = setTimeout(function(){ddCollapse(c)},50); }}function ddCollapse(c){ c.timer = setInterval(function(){ddSlide(c,-1)},DDTIMER);}function cancelHide(id){ var h = document.getElementById(id + '-ddheader'); var c = document.getElementById(id + '-ddcontent'); clearTimeout(h.timer); clearInterval(c.timer); if(c.offsetHeight < c.maxh){ c.timer = setInterval(function(){ddSlide(c,1)},DDTIMER); }}function ddSlide(c,d){ var currh = c.offsetHeight; var dist; if(d == 1){ dist = (Math.round((c.maxh - currh) / DDSPEED)); }else{ dist = (Math.round(currh / DDSPEED)); } if(dist <= 1 && d == 1){ dist = 1; } c.style.height = currh + (dist * d) + 'px'; c.style.opacity = currh / c.maxh; c.style.filter = 'alpha(opacity=' + (currh * 100 / c.maxh) + ')'; if((currh < 2 && d != 1) || (currh > (c.maxh - 2) && d == 1)){ clearInterval(c.timer); }}</script></head><body><dl class="dropdown"> <dt id="one-ddheader" onmouseover="ddMenu('one',1)" onmouseout="ddMenu('one',-1)">源码下载</dt> <dd id="one-ddcontent" onmouseover="cancelHide('one')" onmouseout="ddMenu('one',-1)"> <ul> <li><a href="#" class="underline">最新源码</a></li> <li><a href="#" class="underline">下载排行</a></li> <li><a href="#" class="underline">脚本资源</a></li> <li><a href="#">Ajax实例</a></li> </ul> </dd></dl><dl class="dropdown"> <dt id="two-ddheader" onmouseover="ddMenu('two',1)" onmouseout="ddMenu('two',-1)">网页特效</dt> <dd id="two-ddcontent" onmouseover="cancelHide('two')" onmouseout="ddMenu('two',-1)"> <ul> <li><a href="#" class="underline">菜单导航</a></li> <li><a href="#" class="underline">层和布局</a></li> <li><a href="#" class="underline">图片特效</a></li> </ul> </dd></dl></body></html>希望本文所述对大家JavaScript程序设计有所帮助。