//写入cookie
function writecookie(str)
{
	document.cookie ="stylecss="+escape(str);
}
//读取cookie
function readcookie()
{
	var mycookie=document.cookie;
		if(mycookie.indexOf("stylecss=")>=0)
		{
			mycookie=mycookie.substr(mycookie.indexOf("stylecss=")+9,12);
			css(unescape(mycookie));
		}
}
//设置样式
function css(str)
{
  var i,obj;
		obj=document.getElementsByTagName("LINK");//得到所有的link
	//遍历所有link
	for(i=0;i<obj.length;i++)
		{
			//判断是否是css
				if(obj[i].getAttribute("rel")=="stylesheet"&&obj[i].getAttribute("title"))
				{
					
					if (obj[i].getAttribute("title")==str) //激活
					{
						obj[i].disabled = false;
						writecookie(str);
					}
					else
					{ //失效
						obj[i].disabled = true;
					}

				}
		}
}
readcookie();