public static AppUser LogInUser(string userName, string password, string locationCode)
        {
            try
            {
                AppUser         loggedInUser = null;
                string          dbMessage    = string.Empty;
                DBParameterList dbParam      = new DBParameterList();
                dbParam.Add(new DBParameter(Common.PARAM_DATA, userName, DbType.String));
                dbParam.Add(new DBParameter(Common.PARAM_DATA2, string.Empty, DbType.String));
                dbParam.Add(new DBParameter(Common.PARAM_DATA3, string.Empty, DbType.String));
                dbParam.Add(new DBParameter(Common.PARAM_OUTPUT, string.Empty, DbType.String, ParameterDirection.Output, Common.PARAM_OUTPUT_LENGTH));

                using (DataTaskManager dt = new DataTaskManager())
                {
                    object returnObject = dt.ExecuteScalar(SP_USER_SEARCH, dbParam);

                    dbMessage = (returnObject == null)? string.Empty:returnObject.ToString();
                    if (dbMessage != string.Empty)
                    {
                        if ((new CryptographyManager(CryptographyProviderType.SymmetricCryptoProvider)).Decrypt(dbMessage).CompareTo(password) == 0)
                        {
                            loggedInUser = AppUser.Search(userName, locationCode);
                        }
                    }
                }
                return(loggedInUser);
            }
            catch (Exception ex)
            {
                throw ex;
            }
        }