JavaScript实现带箭头标识的多级下拉菜单效果
作者：企鹅
这篇文章主要介绍了JavaScript实现带箭头标识的多级下拉菜单效果,可实现横向与纵向箭头的形式标识选中菜单项位置的功能,涉及javascript针对页面元素位置的判定与样式动态操作技巧,需要的朋友可以参考下
本文实例讲述了JavaScript实现带箭头标识的多级下拉菜单效果。分享给大家供大家参考。具体如下：
这是一个支持多级显示的JS菜单，鼠标移向带有小三角的菜单项，可下拉出二级子菜单项，在该主菜单的上方会显示标记，指引当前的位置，本菜单代码使用了一个JS类，可根据代码地址自行下载，这个菜单未在网上测试，用在自己的网站里可能要修改代码。
运行效果截图如下：
在线演示地址如下：
http://demo.jb51.net/js/2015/js-focus-m-select-menu-nav-codes/
具体代码如下：
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<title>多级展开的横向菜单</title>
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#imenus0 ul .imeas span,#imenus0 ul .imeasj span {background-image:url(images/sample3_sub_arrow.gif); width:5px; height:7px; left:-5px; top:3px; background-repeat:no-repeat;background-position:top left;}
#imenus0 ul li:hover .imeas span,#imenus0 ul li a.iactive .imeasj span {background-image:url(images/sample3_sub_arrow.gif); background-repeat:no-repeat;background-position:top left;}
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</style><!--end-->
</head>
<body>
<div class="imrcmain0 imgl" style="width:580px;z-index:999999;position:relative;"><div class="imcm imde" id="imouter0"><ul id="imenus0">
<li class="imatm" style="width:145px;"><a class="" href="#"><span class="imea imeam"><span></span></span>Who We Are</a>
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<li><a href="#">Fire & Security</a></li>
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<li><a href="#">Engineered Producs</a></li>
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希望本文所述对大家的javascript程序设计有所帮助。