用cookie存取变量

function SetCookie( name, value)//两个参数，一个是cookie的名子，一个是值{    var Days = 1; //此 cookie 将被保存 1 天    var exp  = new Date();    //new Date("December 31, 9998");    exp.setTime(exp.getTime() + Days*24*60*60*1000);    document.cookie = name + "="+ escape (value) + ";expires=" + exp.toGMTString();}function getCookie(name)//取cookies函数        {    var arr = document.cookie.match(new RegExp("(^| )"+name+"=([^;]*)(;|$)"));    if(arr != null)    return unescape(arr[2]);          return null;}function delCookie(name)//删除cookie{    var exp = new Date();    exp.setTime(exp.getTime() - 1);    var cval=getCookie(name);    if(cval!=null) document.cookie= name + "="+cval+";expires="+exp.toGMTString();}