function setCookie(name,value,days){

        var exp=new Date();

        exp.setTime(exp.getTime() + days*24*60*60*1000);

        var arr=document.cookie.match(new RegExp("(^| )"+name+"=([^;]*)(;|$)"));

        document.cookie=name+"="+escape(value)+";expires="+exp.toGMTString();

}

function getCookie(name){

        var arr=document.cookie.match(new RegExp("(^| )"+name+"=([^;]*)(;|$)"));

        if(arr!=null){

                return unescape(arr[2]);

                return null;

        }

}

function delCookie(name){

        var exp=new Date();

        exp.setTime(exp.getTime()-1);

        var cval=getCookie(name);

        if(cval!=null){

                document.cookie=name+"="+cval+";expires="+exp.toGMTString();

        }

}