function setCookie(cnameList,cvalueList,exdays){

    var d = new Date();

    d.setTime(d.getTime()+(exdays*24*60*60*1000));

    var expires = "expires="+d.toGMTString();

    var tem = '';

    for(var i=0;i<cnameList.length;i++){

        tem += cnameList[i] + "=" +cvalueList[i] + "; "

    }

    //注意下面写cookie ，cookie原值会被覆盖

    document.cookie = tem + expires;

}

function getCookie(cname){

    var name = cname + "=";

    var ca = document.cookie.split(';');

    for(var i=0; i<ca.length; i++) {

        var c = ca[i].trim();

        if (c.indexOf(name)==0){

            return c.substring(name.length,c.length);

        }

    }

    return "";

}