function setCookie(cookieName, cookieValue, cookieExpire){
    document.cookie = cookieName + "=" + escape(cookieValue) + ((cookieExpire == null)?"":("; expires=" + cookieExpire.toGMTString()));
}

function getCookie(cookieName) {
    var search = cookieName + "=";
    if (document.cookie.length > 0) {
        offset = document.cookie.indexOf(search);
        if (offset != -1) {
            offset += search.length;
            end = document.cookie.indexOf(";", offset);
            if (end == -1)
                end = document.cookie.length;
            return unescape(document.cookie.substring(offset, end));
        }
    }
    return false;
}

function delCookie(cookieName, cookieValue){
    today = new Date();
    cookieExpire = new Date();
    cookieExpire.setTime(today.getTime());
    setCookie(cookieName, cookieValue, cookieExpire);
}