本文实例讲述了JS实现灵巧的下拉导航效果代码。分享给大家供大家参考。具体如下：
这是一款基于JS实现下拉菜单，是一款灵巧的网站导航条，支持二级显示，向下滑动显示，经典的下拉菜单，JS和CSS共同编写实现，Li菜单列表风格，便于修改，兼容各大主流浏览器，相信你也会喜欢的。
运行效果截图如下：
在线演示地址如下：
http://demo.phpstudy.net/js/2015/js-down-nav-blue-menu-style-codes/
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=utf-8" />
<title>js暗蓝色下拉导航菜单</title>
<style>
@charset "utf-8";
body{padding:0px;margin:0px;}
body{font-family:Arial, Helvetica, sans-serif;font-size:9pt;background-color:#3A4954;}
ul,li{padding:0px;margin:0px;list-style-type: none;}
* a{text-decoration: none;color:#CFE0EE;}
a:hover{color:#F09C42;}
a:hover{color:#F09C42;}
#navMenu{width:100%;height: 34px;line-height: 34px;display:block;overflow:hidden;background-image: url(images/nav_bg.jpg);background-repeat:repeat-x;background-position: left top;}
#navMenu ul{width:95%;
margin-left:16px;}
#navMenu .onelink{background-image:none;}
#navMenu li{width:90px;text-align:center;float: left;line-height: 34px;height: 34px;background-image: url(images/nav_fg.jpg);background-repeat: no-repeat;background-position: 0 center;margin-left: -2px;}
#navMenu li a{color:#6CA7C7;font-family: "宋体";padding-right: 1em;padding-left: 1em;margin-left: 2px;display: block;}
#navMenu li a:hover, #navMenu li.hover a{background-image: url(images/hover_bg.jpg);background-repeat:repeat-x;background-position: center top;text-decoration: none;color:#FF7B0E;}
.dropMenu{position:absolute;top: 0;z-index:100;width: 110px;visibility: hidden;
margin-top: -1px;margin-left:-2px;border: 1px solid #4D5B66;border-top: 0px solid #3CA2DC;background-color: #0D1C31;padding-top:6px;padding-bottom:6px;filter: Alpha(Opacity=85);}
.dropMenu li{margin-top:2px;margin-bottom:4px;padding-left:6px;}
.dropMenu li a{width: 92%;display: block;text-align:center;color: black;padding: 4px 0 4px 0px;color:#6CA7C7;border-bottom: 1px dashed #4D5B66;}
.dropMenu+li a{border-top:none;}
* html .dropMenu a{width: 100%;color:#6CA7C7;}
.dropMenu a:hover{text-decoration: underline;color:#F09C42;}
.hdo{width:100%;
height:auto;
display:block;
overflow:hidden;}
</style>
<script type='text/javascript' src='js/dropdown.js'></script>
</head>
<body>
<div id="navMenu">
<ul>
<li class="onelink"><a href='#' target="_blank">主页</a></li>
<li><a href='#' target="_blank">HTML+CSS模板</a></li>
<li><a href='#' rel='dropmenu1' target="_blank">JS代码</a></li>
<li><a href='#' rel='dropmenu2' target="_blank">电子商务</a></li>
<li><a href='#' >SEO优化</a></li>
<li><a href='#' rel='dropmenu3' target="_blank">建站技巧</a></li>
<li><a href='#' target="_blank">网络营销</a></li>
</ul>
</div>
<ul id="dropmenu1" class="dropMenu">
<li><a href="#" target="_blank">导航菜单</a></li>
<li><a href="#" target="_blank">焦点幻灯片</a></li>
<li><a href="#" target="_blank">网页特效</a></li>
<li><a href="#" target="_blank">广告代码</a></li>
</ul>
<ul id="dropmenu2" class="dropMenu">
<li><a href="#" target="_blank">企业类网站</a></li>
<li><a href="#" target="_blank">行业类网站</a></li>
<li><a href="#/" target="_blank">BLOG类网站</a></li>
<li><a href="#" target="_blank">门户类网站</a></li>
<li><a href="#" target="_blank">商城类网站</a></li>
</ul>
<ul id="dropmenu3" class="dropMenu">
<li><a href="#" target="_blank">HTML技巧</a></li>
<li><a href="#" target="_blank">CSS技巧</a></li>
<li><a href="#" target="_blank">CMS建站技巧</a></li>
<li><a href="#" target="_blank">其他技巧</a></li>
</ul>
<script type="text/javascript">cssdropdown.startchrome("navMenu")</script>
<!--//nav-->
</body>
</html>
希望本文所述对大家的javascript程序设计有所帮助。