/// <summary>
        /// Sets RegisteredStaff IsEnabled value
        /// </summary>
        /// <param name="rsID"></param>
        /// <param name="IsEnabled"></param>
        static public bool UpdateAccountEnabled(int rsID, bool IsEnabled)
        {
            try
            {
                var db = Connection();

                RegisteredStaff rs = db.RegisteredStaffs.FirstOrDefault(r => r.RegisteredStaffID.Equals(rsID));
                rs.IsEnabled = IsEnabled;

                db.SubmitChanges();
                return(true);
            }
            catch (Exception e)
            {
                Console.WriteLine(e);
                return((bool)GetDefaultReturn(typeof(bool)));
            }
        }
        static public bool UpdateRegisteredStaff(int rSftaffID, string username, string password)
        {
            try
            {
                var             db = Connection();
                RegisteredStaff rs = db.RegisteredStaffs.FirstOrDefault(r => r.RegisteredStaffID.Equals(rSftaffID));

                rs.RUsername = username.ToLower();
                rs.RPassword = password;

                db.SubmitChanges();
                return(true);
            }
            catch (Exception e)
            {
                Console.WriteLine(e);
                return((bool)GetDefaultReturn(typeof(bool)));
            }
        }
        /// <summary>
        /// Register new employee in RegisteredStaff. Returns true if successful (non duplicate).
        /// </summary>
        /// <param name="username"></param>
        /// <param name="password"></param>
        /// <param name="roleID"></param>
        /// <param name="departmentID"></param>
        /// <param name="allStaffID"></param>
        static public bool RegisterRStaff(string username, string password, int allStaffID)
        {
            try
            {
                var db = Connection();

                //check if username already exists
                var query = from staff in db.RegisteredStaffs where staff.RUsername == username select staff;

                if (query.Any())
                {
                    //if username exists, exit
                    return(false);
                }
                else
                {
                    //if username not taken, create account
                    RegisteredStaff newStaff = new RegisteredStaff
                    {
                        RUsername  = username,
                        RPassword  = password,
                        AllStaffID = allStaffID,
                        IsActive   = true,
                        IsEnabled  = true
                    };

                    db.RegisteredStaffs.InsertOnSubmit(newStaff);
                    db.SubmitChanges();
                    return(true);
                }
            }
            catch (Exception e)
            {
                Console.WriteLine(e);
                return((bool)GetDefaultReturn(typeof(bool)));
            }
        }