Code execution is not going down

Question

I have a code below and it has strange behavior,Line of code after closing of While Loop is not executing. If i write those lines before While loop they got executed. I have searched a lot on this issue but failed.

if ((Convert.ToInt32(newDt.Rows[i]["qty"])) > (Convert.ToInt32(newDt1.Rows[i]["qty"])))
            {
                k_batch = Convert.ToInt32(newDt.Rows[i]["batch_num"]);
                label20.Content = k_batch.ToString();
                var dqty = (from row in Addition_result.AsEnumerable()      //retriving value from DataTable
                            where row.Field<int>("batch_num") == k_batch
                            select row.Field<int>("qty")).FirstOrDefault();

                dqty_y = Convert.ToInt32(dqty);
                label16.Content = dqty_y.ToString();


                    con.Open();

                    SqlCommand cmd1 = new SqlCommand("SELECT quantity,sold_qty,left_qty FROM batch WHERE id='" + k_batch + "'", con);
                    SqlDataReader batch_qty_details = null;
                    batch_qty_details = cmd1.ExecuteReader();

                    while (batch_qty_details.Read())
                    {
                        label16.Content = dqty_y.ToString();
                        batch_qty = Convert.ToInt32(batch_qty_details["quantity"]);
                        batch_left = Convert.ToInt32(batch_qty_details["left_qty"]);
                        batch_sold = Convert.ToInt32(batch_qty_details["sold_qty"]);
                    }  //code after this is not executing

                label18.Content = batch_left.ToString();
                label19.Content = batch_sold.ToString();
                label21.Content = dqty_y.ToString();
                label22.Content = batch_qty.ToString();
                label16.Content = batch_sold + dqty_y;
                label17.Content = batch_left - dqty_y;

                if (((batch_sold + dqty_y) <= batch_qty) && ((batch_left - dqty_y) >= 0))
                {
                    SqlCommand command = new SqlCommand("update batch set sold_qty=sold_qty+@soldqty2, left_qty=left_qty-@soldqty2 where id=@id2", con);
                    command.Parameters.AddWithValue("@soldqty2", Convert.ToInt32(dqty_y));
                    command.Parameters.AddWithValue("@id2", Convert.ToInt32(k_batch));
                    rexe = command.ExecuteNonQuery();
                }
                else
                {
                    MessageBox.Show("Please Check you Ordered Quantity !");
                }



                con.Close();

            }
        }

Answer 1

Actually there was issue that connection state was already Open and i was trying to open it again. So then i used try-catch block it told me that connection is already open. Now i have changed my code and here it is.

if ((Convert.ToInt32(newDt.Rows[i]["qty"])) > (Convert.ToInt32(newDt1.Rows[i]["qty"])))
            {
                k_batch = Convert.ToInt32(newDt.Rows[i]["batch_num"]);
                label20.Content = k_batch.ToString();
                var dqty = (from row in Addition_result.AsEnumerable()      //retriving value from DataTable
                            where row.Field<int>("batch_num") == k_batch
                            select row.Field<int>("qty")).FirstOrDefault();

                dqty_y = Convert.ToInt32(dqty);
                label16.Content = dqty_y.ToString();

                try
                {
                    //con.Open();

                    SqlCommand cmd1 = new SqlCommand("SELECT quantity,sold_qty,left_qty FROM batch WHERE id='" + k_batch + "'", con);
                    SqlDataReader batch_qty_details = null;
                    batch_qty_details = cmd1.ExecuteReader();

                    while (batch_qty_details.Read())
                    {
                        label16.Content = dqty_y.ToString();
                        batch_qty = Convert.ToInt32(batch_qty_details["quantity"]);
                        batch_left = Convert.ToInt32(batch_qty_details["left_qty"]);
                        batch_sold = Convert.ToInt32(batch_qty_details["sold_qty"]);
                    }
                    con.Close();
                }
                catch(Exception EX)
                {
                    MessageBox.Show(EX.ToString());

                }
                label18.Content = batch_left.ToString();
                label19.Content = batch_sold.ToString();
                label21.Content = dqty_y.ToString();
                label22.Content = batch_qty.ToString();
                label16.Content = batch_sold + dqty_y;
                label17.Content = batch_left - dqty_y;


                if (((batch_sold + dqty_y) <= batch_qty) && ((batch_left - dqty_y) >= 0))
                {
                    con.Open();
                    SqlCommand command = new SqlCommand("update batch set sold_qty=sold_qty+@soldqty2, left_qty=left_qty-@soldqty2 where id=@id2", con);
                    command.Parameters.AddWithValue("@soldqty2", Convert.ToInt32(dqty_y));
                    command.Parameters.AddWithValue("@id2", Convert.ToInt32(k_batch));
                    rexe = command.ExecuteNonQuery();
                }
                else
                {
                    check_qty = -1;


                }






            }