目录树的实现程序

				
				
				阿赖的菜单控件
				
				
				
				
				
				
				
				
				经典Windows样式菜单应用示例
				点击上面的菜单栏显示相应的菜单，点击鼠标右键可显示右键菜单！
				程序代码：
				
				
				
				copywrite by 赖国欣 2003/6 All right reserved
				Email: a@lai.com.cn website: 
				http://www.9499.net/ 
				
					/***********************************
						经典Windows样式菜单应用示例
					赖国欣设计于2003年6月，保留所有权利！
					************************************/
					
					/*建立5个菜单实例对象*/
					var m1=new alai_menu()
					var m2=new alai_menu()
					var m3=new alai_menu()
					var m4=new alai_menu()
					var m5=new alai_menu()
					var m6=new alai_menu()
					
					/*菜单栏*/
					var mc=new menu_bar(10,20);
					mc.add("菜单功能演示",m1)
					mc.add("网址收藏",m2)
					mc.add("其它",m3)
					
					/*添加菜单项*/
					m1.add("显示子菜单","sub",m3)
					m1.add("执行JS命令","js","alert('谢谢使用');")
					m1.add("隐藏菜单","hide")
					m1.add("去google一下","url","http://www.google.com","_blank")
					m1.seperate()//加分隔线
					var item=m1.add("enable=false","js","alert('谢谢使用');")
						item.enable=false
					var itemDel=m1.add("请把我移除")
						itemDel.execute=function(){itemDel.remove();}
					m1.seperate()//加分隔线
					m1.add("动态增加菜单项...").execute=function(){var txt=prompt("输入文字：");m1.add(txt);}
					
				
					m2.addLink("http://msdn.microsoft.com/library/default.asp","MSDN Library")
					m2.addLink("http://www.csdn.net","程序员大本营")
					m2.addLink("http://www.google.net")
					m2.addLink("http://www.devarticles.com","DevArticles")
					
					
					m3.add("无限级子菜单演示","sub",m4)
					m3.seperate()
					m3.add("刷新页面")
					m3.add("添加到收藏夹")
					m3.add("设为首页")
					m3.seperate()
					m3.addLink("http://www.9499.net","9499.NET主页")
					m3.addLink("http://www.9499.net?go=ly","访客留言中心")
					m3.addLink("http://www.9499.net?go=tc","在线教程")
					
					m4.add("无限级子菜单演示","sub",m5)
					m4.seperate()
					m4.add("刷新页面")
					m4.add("添加到收藏夹")
					m4.add("设为首页")
					m4.seperate()
					m4.addLink("http://www.9499.net","9499.NET主页")
					m4.addLink("http://www.9499.net?go=ly","访客留言中心")
					m4.addLink("http://www.9499.net?go=tc","在线教程")
					
					m5.add("无限级子菜单演示","sub",m3)
					m5.seperate()
					m5.add("刷新页面")
					m5.add("添加到收藏夹")
					m5.add("设为首页")
					m5.seperate()
					m5.addLink("http://www.9499.net","9499.NET主页")
					m5.addLink("http://www.9499.net?go=ly","访客留言中心")
					m5.addLink("http://www.9499.net?go=tc","在线教程")
					
					m3.item[1].execute=m4.item[1].execute=m5.item[1].execute=function(){self.history.go(0);}
					m3.item[2].execute=m4.item[2].execute=m5.item[2].execute=function()
					{
						window.external.addFavorite("http://www.9499.net","创意无限，精彩无限--WWW.9499.NET");
					}
					m3.item[3].execute=m4.item[3].execute=m5.item[3].execute=function()
					{
						event.srcElement.style.behavior="url(#default#homepage)";
						event.srcElement.setHomePage("http://www.9499.net");
					}
					
					/*显示右键菜单*/
					document.body.oncontextmenu=function(){event.returnValue=false;}
					document.body.onmousedown=function(){if(event.button==2)m3.show();}
					
					/*显示源程序*/
					var script=document.getElementsByTagName("SCRIPT")
					var sCode=script[1].innerHTML
					sCode=sCode.replace(//g,">")
					sCode=sCode.replace(/([A-Za-z0-9>					sCode=sCode.replace(/\t/g,"    ")
					sCode=sCode.replace(/(\/\*)/g,"$1")
					sCode=sCode.replace(/(\*\/)/g,"$1")
					sCode=sCode.replace(/\n/g,"")
					divCode.innerHTML=sCode;