public static string KiemTraHoaDon(int maLichBan) { DbCommand command = DataAccessCode.CreateCommand(); command.CommandText = "dbo.KiemTraHoaDon"; //// create a new parameter DbParameter param = command.CreateParameter(); param.ParameterName = "@MaLichBan"; param.Value = maLichBan; param.DbType = DbType.Int32; command.Parameters.Add(param); string flag = DataAccessCode.ExecuteScalar(command); return(flag); }