public static void UpdateStage(StagesClass St)
 {
     Conn.Open();
     string query = String.Format("Update [dbo].[Stages] set NumberOfSets={0}, NumberOfExercices={1},TypeOfExercices={2} where Training_Id={3} and TypeOfStage='{4}'", St.GetNumberOfSets(), St.GetNumberOfExercices(), St.GetTypeOfExercice(), St.GetTrainingId(), St.GetTypeOfStage());
     command = new SqlCommand(query, Conn);
     command.ExecuteNonQuery();
     Conn.Close();
 }
 public static void InsertStage(StagesClass St)
 {
     Conn.Open();
     string query = String.Format("Insert into [dbo].[Stages](NumberOfSets,NumberOfExercices,TypeOfExercices,Training_Id,TypeOfStage) values({0},{1},{2},{3},'{4}')",St.GetNumberOfSets(),St.GetNumberOfExercices(),St.GetTypeOfExercice(),St.GetTrainingId(),St.GetTypeOfStage());
     command = new SqlCommand(query, Conn);
     command.ExecuteNonQuery();
     Conn.Close();
 }