JS实现适合于后台使用的动画折叠菜单效果

本文实例讲述了JS实现适合于后台使用的动画折叠菜单效果。分享给大家供大家参考。具体如下：
这是一款适合于后台使用的动画折叠菜单，代码超简，无jQuery，展开与折叠效果平滑。本演示中有两组菜单，向大家展示如何在一个网页中布局两个菜单，整体效果以及兼容性还算可以，希望在实际应用中不会出现什么问题。
运行效果截图如下：

在线演示地址如下：
http://demo.jb51.net/js/2015/js-ht-control-animate-zd-menu-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>适合于后台使用的动画折叠菜单</title><script type="text/javascript"> function FOLDMenu（id,onlyone）{if（！document.getElementById || ！document.getElementsByTagName）{return false;}this.menu=document.getElementById（id）;this.submenu=this.menu.getElementsByTagName（"ul"）;this.speed=3;this.time=10;this.onlyone=onlyone==true?onlyone:false;this.links = this.menu.getElementsByTagName（"a"）; } FOLDMenu.prototype.init=function（）{var mainInstance = this;for（var i=0;i<this.submenu.length;i++）{ this.submenu[i].getElementsByTagName（"span"）[0].onclick=function（）{mainInstance.toogleMenu（this.parentNode）; };}for（var i=0;i<this.links.length;i++）{ this.links[i].onclick=function（）{this.className = "current";mainInstance.removeCurrent（this）; }} } FOLDMenu.prototype.removeCurrent = function（link）{ for （var i = 0; i < this.links.length; i++）{if （this.links[i] ！= link）{ this.links[i].className = " "; } } } FOLDMenu.prototype.toogleMenu=function（submenu）{if（submenu.className=="open"）{ this.closeMenu（submenu）;}else{ this.openMenu（submenu）;} } FOLDMenu.prototype.openMenu=function（submenu）{var fullHeight=submenu.getElementsByTagName（"span"）[0].offsetHeight;var links = submenu.getElementsByTagName（"a"）;for （var i = 0; i < links.length; i++）{ fullHeight += links[i].offsetHeight;} var moveBy = Math.round（this.speed * links.length）;var mainInstance = this; var intId = setInterval（function（） {var curHeight = submenu.offsetHeight;var newHeight = curHeight + moveBy;if （newHeight <fullHeight）{submenu.style.height = newHeight + "px"; }else {clearInterval（intId）;submenu.style.height = ""; submenu.className = "open"; } }, this.time）; this.collapseOthers（submenu）; } FOLDMenu.prototype.closeMenu=function（submenu）{ var minHeight=submenu.getElementsByTagName（"span"）[0].offsetHeight; var moveBy = Math.round（this.speed * submenu.getElementsByTagName（"a"）.length）; var mainInstance = this;var intId = setInterval（function（） { var curHeight = submenu.offsetHeight; var newHeight = curHeight - moveBy; if （newHeight > minHeight）{submenu.style.height = newHeight + "px"; }else {clearInterval（intId）;submenu.style.height = ""; submenu.className = ""; } }, this.time）;} FOLDMenu.prototype.collapseOthers = function（submenu）{if（this.onlyone）{ for （var i = 0; i < this.submenu.length; i++）{if （this.submenu[i] ！= submenu）{ this.closeMenu（this.submenu[i]）; } }} }</script><style type="text/css">*{margin:0;padding:0;}.foldmenu{border:1px solid #000;width:150px;margin:50px;}.foldmenu ul{list-style-type:none;height:25px;line-height:25px;overflow:hidden;cursor:pointer;}.foldmenu ul.open{height:auto;}.foldmenu ul span{display:block;padding-left:5px}.foldmenu ul li{border-bottom:1px solid #DDDDDD;}.foldmenu li a{background-color:#EEEEEE;color:#006666;display:block;padding:5px 10px;text-decoration:none;text-align:center;}.foldmenu li a:hover{background-color:#006666;color:#ffffff;}.foldmenu li a.current{background-color:#006666;color:#ffffff;}</style></head><body><div id="foldmenu" class="foldmenu" style="float:left;"> <ul class="open"><span>编程天地</span> <li><a href="#">电子书籍</a></li> <li><a href="#">源码乐园</a></li> </ul> <ul><span>中国门户</span> <li><a href="#">百度搜索</a></li> <li><a href="#">新浪新闻</a></li><li><a href="#">腾讯QQ</a></li> </ul> <ul><span>音乐网站</span> <li><a href="#">百度音乐</a></li> <li><a href="#">QQ163</a></li> </ul></div><div id="foldmenu2" class="foldmenu" style="float:right;"> <ul class="open"><span>世界大学</span> <li><a href="#">剑桥</a></li> <li><a href="#">牛津</a></li><li><a href="#">哈佛</a></li> <li><a href="#">麻省理工</a></li> </ul> <ul><span>中国大学</span> <li><a href="#">北大</a></li> <li><a href="#">清华</a></li><li><a href="#">港大</a></li> </ul> <ul><span>世界好车</span> <li><a href="#">宝马</a></li> <li><a href="#">奔驰</a></li> <li><a href="#">奥迪</a></li> </ul> <ul><span>开源论坛</span> <li><a href="#">PhpWind</a></li> <li><a href="#">Discuz！</a></li> </ul></div><script type="text/javascript">window.onload = function（） { myMenu = new FOLDMenu（"foldmenu",true）; myMenu.init（）; myMenu2 = new FOLDMenu（"foldmenu2"）; myMenu2.init（）;};</script></body></html>

希望本文所述对大家的JavaScript程序设计有所帮助。