public void loadSoldItems() { try { double total = 0; dataGridSoldItems.Rows.Clear(); using (MySqlDataReader reader = pos.showSoldItems(dateTimePicker1.Value.ToString("yyyy-MM-dd"), dateTimePicker2.Value.ToString("yyyy-MM-dd"), username.Text)) { while (reader.Read()) { total += Convert.ToDouble(reader["total"].ToString()); dataGridSoldItems.Rows.Add(reader["transaction_id"].ToString(), reader["transactionNo"].ToString(), reader["products_id"].ToString(), reader["description"].ToString(), reader["price"].ToString(), reader["quantity"].ToString(), reader["discount"].ToString(), reader["total"].ToString()); } } totalSales.Text = total.ToString("#,##0.00"); } catch (Exception ex) { MessageBox.Show(ex.Message); } }