public void updateTable() { DateTime date = DateTime.Now; if (dtStartDate.Value.Date < dtEndDate.Value.Date && dtStartDate.Value.Date >= date) { Helper helper = new Helper(); ActionWithDB api = new ActionWithDB(); SqlDataReader reader = api.checkingFreeSpace(dtStartDate.Value.Date, dtEndDate.Value.Date); if (tbClubCard.Text != "") { int discont = api.getDiscont(dtStartDate.Value.Date, tbClubCard.Text); helper.clearDataGridView(dGVFreePlace); int i = 0; while (reader.Read()) { dGVFreePlace.RowCount++; dGVFreePlace.Rows[i].Cells[0].Value = reader[0].ToString(); dGVFreePlace.Rows[i].Cells[1].Value = reader[1].ToString(); dGVFreePlace.Rows[i].Cells[2].Value = reader[2].ToString(); dGVFreePlace.Rows[i].Cells[3].Value = discont; dGVFreePlace.Rows[i].Cells[4].Value = api.getTotalCost(discont, dGVFreePlace.Rows[i].Cells[2].Value.ToString()); i++; } } } else { Helper helper = new Helper(); helper.clearDataGridView(dGVFreePlace); } }