private void AddRoomButton_Click(object sender, EventArgs e) { if (RoomPriceTextBox.Text == "") { MessageBox.Show("Please, enter at least the room type, price and associated department."); } else { int r = controllerObj.A_AddRoom((string)RoomTypeComboBox.SelectedItem, RoomSizeTextBox.Text.ToString(), Convert.ToInt32(RoomPriceTextBox.Text.ToString()), (int)depComboBox.SelectedValue); if (r > 0) { MessageBox.Show("Room added successfully."); DataTable dt1 = controllerObj.SelectRoomIDs(); RoomsComboBox.DataSource = dt1; RoomsComboBox.DisplayMember = "RID"; RoomsComboBox.ValueMember = "RID"; } else { MessageBox.Show("Error in adding room."); } } }