suppresion a partir dun code c#

 private void Delete_Click(object sender, EventArgs e)
        {
            
           
            try
            {
               
             DateTime D1 = Convert.ToDateTime(yearstart.Text + "/" + monthstart.Text + "/" + daystart.Text + " 00:00:00.000");
               
             DateTime D2 = Convert.ToDateTime(yearend.Text + "/" + monthend.Text + "/" + dayend.Text + " 00:00:00.000");


             // SqlCommand myCommand = new SqlCommand("select* from  Operation,Lots,Data where Operation.Num=Lots.Num and Data.Date textBox1 Operation.Start_Date and Operation.End_Date and Data.Date_Now textBox1 "+Convert.ToDateTime(startpurge.Text)+" and "+Convert.ToDateTime(Endpurge.Text), Program.Connexion);
                // SqlCommand myCommand = new SqlCommand("select* from  Operation,Lots,Data where Operation.Num=Lots.Num and Data.Date textBox1 Operation.Start_Date and Operation.End_Date", Program.connexion);
                //  DELETE FROM OpEnCours where Label='" + EtuveASupprimer + "'", Program.connexion);

              /*
                SqlCommand myCommand3 = new SqlCommand("DELETE from  Lots where  Lots.Num in(select Lots.Num from  Operation,Lots where Operation.Num=Lots.Num and Operation.Start_Date between '" + D1 + "' and '" + D2 + "') ", Program.connexion);
                myCommand3.ExecuteReader();
               Program.connexion.Close();*/

                              
               Program.connexion.Open();
               SqlCommand myCommand = new SqlCommand("DELETE from  Live_Operation where End_Date between '" + D1 + "' and '" + D2 + "'", Program.connexion);
                myCommand.ExecuteReader();
                Program.connexion.Close();
                
               Program.connexion.Open();
             
          /* SqlCommand commande = new SqlCommand("DELETE  from  Data where Date_Now between '" + D1 + "' and '" + D2 + "'", Program.connexion);
           commande.ExecuteNonQuery(); */


                richTextBox.Text = "\n Archives between " + monthstart.Text + "/" + daystart.Text + "/" + yearstart.Text + " and " + monthend.Text + "/" + dayend.Text + "/" + yearend.Text + " are deleted succefully...";
            }
            catch (Exception) { richTextBox.Text = "\nNo data... "; }
            Program.connexion.Close();
        }