private async void Button_Click_2(object sender, RoutedEventArgs e) { wResult.Text = ""; Wfin.Visibility = Visibility.Collapsed; rectangle.Visibility = System.Windows.Visibility.Visible; LongRun lr = new LongRun(); long i = await lr.CountAsync3(); wResult.Text = i.ToString(); rectangle.Visibility = System.Windows.Visibility.Collapsed; Wfin.Visibility = Visibility.Visible; }