protected void DoAddSubmitPromotion()
        {
            Promotion p = new Promotion();

            // validate data
            p._promotionName = Request["promotion_name"];
            p._promotionDesc = Request["promotion_desc"];
            p._cost          = Int32.Parse(Request["cost"]);
            p._isActive      = Request["is_active"] != null ? true : false;

            // read selected course
            ArrayList idList = new ArrayList();

            for (int i = 0; i < Request.Form.AllKeys.Length; i++)
            {
                if (Request.Form.AllKeys[i].StartsWith("course"))
                {
                    string s = Request.Form.AllKeys[i].Substring(6);
                    idList.Add(s);
                }
            }
            p._courses = new Course[idList.Count];
            int n = 0;

            foreach (string id in idList)
            {
                try
                {
                    Course c = new Course();
                    c._courseID     = Int32.Parse(id);
                    p._courses[n++] = c;
                }
                catch (Exception e) { Console.WriteLine(e.StackTrace); }
            }

            // Save to DB
            DBManager db = new MySQLDBManager(Config.DB_SERVER, Config.DB_NAME, Config.DB_USER, Config.DB_PASSWORD, Config.DB_CHAR_ENC);

            db.Connect();
            p.AddToDB(db);
            db.Close();
        }