function createCookie(name, value, expiredays) {
  var todayDate= new Date();
  todayDate.setDate(todayDate.getDate() + expiredays );
  document.cookie = name + " = " + value + "; expires=" + todayDate.toGMTString() + ";"
}

function ReadCookie(cookiename) {
  var numOfCookies = document.cookie.length;
  var nameOfCookie = cookiename + "=";
  var cookieLen = nameOfCookie.length;
  var x = 0;
  while (x <= numOfCookies) {
    var y = (x + cookieLen);
    if (document.cookie.substring(x,y) == nameOfCookie)
      return (extractCookieValue(y));
    x = document.cookie.indexOf(" ", x) + 1;
    if (x == 0)
      break;
  }
  return null;
}

function extractCookieValue(val) {
  if ((endOfCookie = document.cookie.indexOf(";", val)) == -1 )
    endOfCookie = document.cookie.length;
  return unescape(document.cookie.substring(val, endOfCookie));
}

function deleteCookie(name, val) {
  var todayDate = new Date();
  todayDate.setDate(todayDate.getDate() - 1);
  document.cookie = name + "=" + val + "; expires=" + todayDate.toGMTString() + ";";
}