private void buttonUserDelete_Click(object sender, EventArgs e)
        {
            if (listBoxUser.SelectedItem is Customer)
            {
                Customer customer = (Customer)listBoxUser.SelectedItem;

                if (customer.EmailAddress != FormController.CurrentCustomer.EmailAddress)
                {
                    if (Feedback.AskCustomerDelete() == DialogResult.Yes)
                    {
                        if (DBController.TryDeleteUser(customer))
                        {
                            UpdateTable();
                            Feedback.SuccessCustomersDelete();
                        }
                        else
                        {
                            Feedback.ErrorDatabaseCustomersDelete();
                        }
                    }
                }
                else
                {
                    Feedback.ErrorCustomersDeleteHimself();
                }
            }
            else
            {
                Feedback.ErrorNoSelectedItem();
            }
        }
 private void buttonUserDelete_Click(object sender, EventArgs e)
 {
     if (DBController.TryCheckOpenBookingsCustomer(FormController.CurrentCustomer, out bool result) && !result)
     {
         if (Feedback.AskOwnCustomerDelete() == DialogResult.Yes)
         {
             if (DBController.TryDeleteUser(FormController.CurrentCustomer))
             {
                 Feedback.SuccessOwnCustomerDelete();
                 FormController.MainView.Close();
             }
             else
             {
                 Feedback.ErrorDatabaseCustomersDelete();
             }
         }
     }
     else
     {
         Feedback.ErrorCustomerDeleteHimselfOpenBookings();
     }
 }