CapDemo.BL.PhaseBL.DeletePhasebyIDContest C# (CSharp) Метод

        public bool DeletePhasebyIDContest(Phase Phase)
        {
            string query = "DELETE FROM [Phase]"
                         + " WHERE [Contest_ID] = '" + Phase.IDContest + "'";
            return DA.DeleteDatabase(query);
        }

        private void deleteSetupToolStripMenuItem_Click(object sender, EventArgs e)
        {
            DialogResult dialogResult = MessageBox.Show("Bạn muốn xóa cuộc thi này không?", "Xóa Thiết Đặt", MessageBoxButtons.YesNo);
            if (dialogResult == DialogResult.Yes)
            {
                Contest Contest = new Contest();
                Phase Phase = new Phase();
                Player Player = new Player();
                Record Record = new Record();

                ContestBL ContestBL = new ContestBL();
                PhaseBL PhaseBl = new PhaseBL();
                PlayerBL PlayerBL = new PlayerBL();
                PhaseQuestionBL PhaseQuestionBL = new PhaseQuestionBL();
                RecordBL RecordBL = new RecordBL();

                Contest.IDContest = Convert.ToInt32(lbl_IDContest.Text);
                Phase.IDContest = Convert.ToInt32(lbl_IDContest.Text);
                Player.IDContest = Convert.ToInt32(lbl_IDContest.Text);
                Record.IDContest = Convert.ToInt32(lbl_IDContest.Text);

                RecordBL.DeleteRecordByIDContest(Record);
                PhaseQuestionBL.DeletePhaseQuestionbyIDContest(Phase);
                PlayerBL.DeletePlayerbyIDContest(Player);
                PhaseBl.DeletePhasebyIDContest(Phase);
                ContestBL.DeleteContestbyID(Contest);
                LoadAll();

                EventHandler delete = onDelete;

                if (delete != null)
                {
                    MyEventArgs args = new MyEventArgs();
                    args.IDNewGame = iD_NewGame;
                    delete(this, args);
                }
            }
        }