function writeSessionCookie (cookieName, cookieValue) {
  if (testSessionCookie()) {
    document.cookie = escape(cookieName) + "=" + escape(cookieValue) + "; path=/";
    return true;
  }
  else return false;
}

function getCookieValue (cookieName) {
  var exp = new RegExp (escape(cookieName) + "=([^;]+)");
  if (exp.test (document.cookie + ";")) {
    exp.exec (document.cookie + ";");
    return unescape(RegExp.$1);
  }
  else return false;
}


function testSessionCookie () {
  document.cookie ="testSessionCookie=Enabled";
  if (getCookieValue ("testSessionCookie")=="Enabled")
    return true 
  else
    return false;
}

function testPersistentCookie () {
  writePersistentCookie ("testPersistentCookie", "Enabled", "minutes", 1);
  if (getCookieValue ("testPersistentCookie")=="Enabled")
    return true  
  else 
    return false;
}

function writePersistentCookie (CookieName, CookieValue, periodType, offset) {

  var expireDate = new Date ();
  offset = offset / 1;
  
  var myPeriodType = periodType;
  switch (myPeriodType.toLowerCase()) {
    case "years":
      expireDate.setYear(expireDate.getFullYear()+offset);
      break;
    case "months":
      expireDate.setMonth(expireDate.getMonth()+offset);
      break;
    case "days":
      expireDate.setDate(expireDate.getDate()+offset);
      break;
    case "hours":
      expireDate.setHours(expireDate.getHours()+offset);
      break;
    case "minutes":
      expireDate.setMinutes(expireDate.getMinutes()+offset);
      break;
    default:
      alert ("Invalid periodType parameter for writePersistentCookie()");
      break;
  } 
  
  document.cookie = escape(CookieName ) + "=" + escape(CookieValue) + "; expires=" + expireDate.toGMTString() + "; path=/";
}  

function deleteCookie (cookieName) {

  if (getCookieValue (cookieName)) writePersistentCookie (cookieName,"Pending delete","years", -1);  
  return true;     
}