private async void save(object sender, EventArgs e) { var brand = brandTextBox.Text; var model = modelTextBox.Text; var type = 0; if (typeComboBox.Text != "") { type = (int)((CarType)Enum.Parse(typeof(CarType), typeComboBox.SelectedItem.ToString())); } var odometer = odometerTextBox.Value; var registrationNumber = registrationNumberTextBox.Text; var efficiency = efficiencyCheckBox.Checked; var isDisabled = isDisabledCheckBox.Checked; var imageUrl = imageUrlTextBox.Text; if (checkCorectness(brand, model, type, odometer, registrationNumber, efficiency, isDisabled)) { await DatabaseService.insertCar(brand, model, type, odometer, registrationNumber, efficiency? 1 : 0, isDisabled? 1 : 0, imageUrl).ContinueWith(task => { bool result = task.Result; if (result) { MessageBox.Show("Samochod zostal zapisany w bazie danych"); if (InvokeRequired) { Invoke(new Action(() => showParent())); } else { showParent(); } } else { MessageBox.Show("Samochod o tej rejestracji juz istnieje w bazie danych!"); } }); } }