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);
     }
 }