Return an object from a popup window

Question

I have a Window which pop-ups another Window. I want the second Window to be able to return an object to the first Window when a button is pressed. How would I do this?

Answer 1

Holy mother of Mars, this took me forever to figure out:

WINDOW 1:

if ((bool)window.ShowDialog() == true)
{
   Window2 content = window.Content as Window2;
   string result = content.result;
   int i = 0;
}

WINDOW 2:

public partial class Window2 : UserControl
{
    public string result
    {
        get { return resultTextBox.Text; }
    }

    public Window2()
    {
        InitializeComponent();
    }

    private void Button_Click(object sender, RoutedEventArgs e)
    {
        Window.GetWindow(this).DialogResult = true;
        Window.GetWindow(this).Close();
    }
}

XAML: