本文实例讲述了js实现带缓冲效果的仿QQ面板折叠菜单代码。分享给大家供大家参考。具体如下：
带缓冲效果的仿QQ面板折叠菜单代码，使用方法：调用效果: Effect(1,2);
其中1为: 被改变对象的id
其中2为: 控制容器的id 可在使用: this.parentNode.id 取得(父标签的id)
注意给对象ID的时候一定不要重复。
运行效果如下图所示：
在线演示地址如下：
http://demo.jb51.net/js/2015/js-buffer-style-qq-menu-codes/
具体代码如下：
<html> <head> <title>带缓冲效果的仿QQ面板折叠菜单代码</title> <script> function $G(Read_Id) { return document.getElementById(Read_Id) } function Effect(ObjectId,parentId){ var Obj_Display = $G(ObjectId).style.display; if (Obj_Display == 'none'){ Start(ObjectId,'Opens'); $G(parentId).innerHTML = "<a href=# onClick=javascript:Effect('"+ObjectId+"','"+parentId+"');>-</a>" }else{ Start(ObjectId,'Close'); $G(parentId).innerHTML = "<a href=# onClick=javascript:Effect('"+ObjectId+"','"+parentId+"');>+</a>" } } function Start(ObjId,method){ var BoxHeight = $G(ObjId).offsetHeight; //获取对象高度 var MinHeight = 5;//定义对象最小高度 var MaxHeight = 130;//定义对象最大高度 var BoxAddMax = 1;//递增量初始值 var Every_Add = 0.15;//每次的递(减)增量 [数值越大速度越快] var Reduce = (BoxAddMax - Every_Add); var Add = (BoxAddMax + Every_Add); //关闭动作** if (method == "Close"){ var Alter_Close = function(){//构建一个虚拟的[递减]循环 BoxAddMax /= Reduce; BoxHeight -= BoxAddMax; if (BoxHeight <= MinHeight){ $G(ObjId).style.display = "none"; window.clearInterval(BoxAction); } else $G(ObjId).style.height = BoxHeight; } var BoxAction = window.setInterval(Alter_Close,1); } //打开动作* else if (method == "Opens"){ var Alter_Opens = function(){ BoxAddMax *= Add; BoxHeight += BoxAddMax; if (BoxHeight >= MaxHeight){ $G(ObjId).style.height = MaxHeight; window.clearInterval(BoxAction); }else{ $G(ObjId).style.display= "block"; $G(ObjId).style.height = BoxHeight; } } var BoxAction = window.setInterval(Alter_Opens,1); } } </script> <style> table{width:192px;overflow:hidden} #control,#control table,#control table td{ font-size:12px;} #control{ width:192px; background-color:#ccc; font-size:12px; font-color:#333333; text-align:center; } #control table{ width:192px; height:20px; overflow:hidden} #control table li{ list-style:none;height:20px;line-height:20px; overflow:hidden} #control table .tabTit{background:#E0E8B8;} #control a { font-weight:normal; font-size:24px; color:#6F7848; text-decoration:none; padding-right:10px;} #control .testLink{ font-weight:bold; font-size:12px} .test{ width:192px;background-color:#f6f6f6;overflow:hidden; } .test li{ list-style:none; color:#000; font-size:13px; line-height:20px;} #control table,.test table{ margin:0 auto; text-align:center} .STYLE1 { font-size: 8px; color: #fff; } </style> </head> <body> <div id="control"> <table width="100%" border="0" cellpadding="0" cellspacing="0"> <tr> <td width="100%" align="center" ><li id="testtab"><a href="#" >+</a> </li><li><a href="#">缓冲菜单</a> </li></td> </tr> </table> </div> <div id="test"> <table width="100%" border="0" cellpadding="4" cellspacing="0" bgcolor="#EEEEEE"> <tr> <td colspan="3" align="center" valign="top"><ul><li>缓冲菜单</li><li>缓冲菜单</li><li>缓冲菜单</li><li>缓冲菜单</li></ul></td> </tr> </table> </div> <br> <div id="control"> <table width="100%" border="0" cellpadding="0" cellspacing="0"> <tr> <td width="100%" align="center" ><li id="test1tab"><a href="#" >+</a> </li><li><a href="#">缓冲菜单</a></li></td> </tr> </table> </div> <div id="test1"> <table width="100%" border="0" cellpadding="4" cellspacing="0" bgcolor="#EEEEEE"> <tr> <td colspan="3" align="center" valign="top"><ul><li>缓冲菜单</li><li>缓冲菜单</li><li>缓冲菜单</li><li>缓冲菜单</li><li>缓冲菜单</li><li>缓冲菜单</li><li>缓冲菜单</li><li>缓冲菜单</li><li>缓冲菜单</li><li>缓冲菜单</li></ul></td> </tr> </table> </div> <br> <div id="control"> <table width="100%" border="0" cellpadding="0" cellspacing="0"> <tr> <td width="100%" align="center" ><li id="test2tab"><a href="#" >+</a> </li><li><a href="#">缓冲菜单</a></li></td> </tr> </table> </div> <div id="test2"> <table width="100%" border="0" cellpadding="4" cellspacing="0" bgcolor="#EEEEEE"> <tr> <td colspan="3" align="center" valign="top"><ul><li>缓冲菜单</li><li>缓冲菜单</li></ul></td> </tr> </table> </div> <br> <div id="control"> <table width="100%" border="0" cellpadding="0" cellspacing="0"> <tr> <td width="100%" align="center" ><li id="test3tab"><a href="#" >+</a> </li><li><a href="#">缓冲菜单</a></li></td> </tr> </table> </div> <div id="test3"> <table width="100%" border="0" cellpadding="4" cellspacing="0" bgcolor="#EEEEEE"> <tr> <td colspan="3" align="center" valign="top"><ul><li>缓冲菜单</li><li>缓冲菜单</li></ul></td> </tr> </table> </div> <br> <div id="control"> <table width="100%" border="0" cellpadding="0" cellspacing="0"> <tr> <td width="100%" align="center" ><li id="test4tab"><a href="#" >+</a> </li><li><a href="#">缓冲菜单</a></li></td> </tr> </table> </div> <div id="test4"> <table width="100%" border="0" cellpadding="4" cellspacing="0" bgcolor="#EEEEEE"> <tr> <td colspan="3" align="center" valign="top"><ul><li>缓冲菜单</li><li>缓冲菜单</li></ul></td> </tr> </table> </div> </body> </html>
希望本文所述对大家的JavaScript程序设计有所帮助。