// Нажатие кнопки "Добавить"
private void bAddService_Click(object sender, EventArgs e)
{
if (tbServiceName.TextLength == 0 || tbCostServicesTab.TextLength == 0)
{
MessageBox.Show("Не все поля заполнены");
return;
}
ServiceController.Save(new ServiceModel(tbServiceName.Text, int.Parse(tbCostServicesTab.Text)));
lbServices.Items.Add(tbServiceName.Text + " " + tbCostServicesTab.Text);
fillServicesComboBox();
}