如何关闭隐藏的窗口（WPF应用程序）？

Question

In my application (WPF) i have this window:

public partial class Window1 : Window and in the Xaml x:Class="WpfApplication1.Window1"

Now, when i switch to and from the main to window 1 and back, i us the Visibility.Hidden and Visibility.Visible to hide them and make them show again to the user.

What i try to do now, is make a test button in the main window, that says: Close Window1. This window is hidden, but i really want to close it in the background. at first i though to just use the Window.Close(); but that does not seem to do the trick.

So, how should i do this in a correct way ? Thank you very much in advance.

EDIT 1 - making question more clear

To open the window1 in my Main window, i use this part

Window1 W1 = null; // Initialise Field.
  public void CalcTabel_Click(object sender, RoutedEventArgs e)
   {
    if (W1 == null)
    {
     W1 = new Window1();
     W1.Hoofdmenu = this;
     W1.checkLang();
     W1.Show();
    }
   else
    {
     W1.checkLang();
     W1.Visibility = Visibility.Visible;
    }
   this.Visibility = Visibility.Hidden;
   }

On window 1 there is a Back button, that has this snip-it of code in it (Where "Hoofdmenu" us the main window):

Hoofdmenu.updateStatistics();
Hoofdmenu.Visibility = Visibility.Visible;
this.Visibility = Visibility.Hidden;

But again, this time when standing in the main window (so window 1 is hidden) i want to close down that window 1. but using W1.Close() does not seem to work. So i am looking for a way to Close that window 1, not change its visibility.

EDIT 2 - Solution

So using W1.Close(); did not work, although a small change this.W1.Close(); did work in fact :)

Answer 1

You can create object of Form2 in window and intialize its visiblity to false.

On click of button you can simpliy say

public partial class MainWindow : Window
  {
    private Window1 window2;

    public MainWindow()
    {
      InitializeComponent();
      this.window2 = new Window1();

      this.window2.Show();
    }

    private void Button_Click(object sender, RoutedEventArgs e)
    {
      this.window2.Visibility = System.Windows.Visibility.Hidden;
    }
  }

to make it visible again

Answer 2

after reading your code, thats not possible the way you want it. the window1 instance is local object. so you cant reach it out side if this method. the best was is to have a close button on window1 with this.close() or you create a global instance in your main window and then check if not null then close it.