How to use a FolderBrowserDialog from a WPF application

Question

I\'m trying to use the FolderBrowserDialog from my WPF application - nothing fancy. I don\'t much care that it has the Windows Forms look to it.

However, when I call

Answer 1

OK, figured it out now - thanks to Jobi whose answer was close, but not quite.

From a WPF application, here's my code that works:

First a helper class:

private class OldWindow : System.Windows.Forms.IWin32Window
{    
    IntPtr _handle;    
    public OldWindow(IntPtr handle)
    {
        _handle = handle;
    }   

    #region IWin32Window Members    
    IntPtr System.Windows.Forms.IWin32Window.Handle
    {
        get { return _handle; }
    }    
    #endregion
}

Then, to use this:

    System.Windows.Forms.FolderBrowserDialog dlg = new FolderBrowserDialog();
    HwndSource source = PresentationSource.FromVisual(this) as HwndSource;
    System.Windows.Forms.IWin32Window win = new OldWindow(source.Handle);
    System.Windows.Forms.DialogResult result = dlg.ShowDialog(win);

I'm sure I can wrap this up better, but basically it works. Yay! :-)

Answer 2

VB.net translation

Module MyWpfExtensions

Public Function GetIWin32Window(this As Object, visual As System.Windows.Media.Visual) As System.Windows.Forms.IWin32Window

    Dim source As System.Windows.Interop.HwndSource = System.Windows.PresentationSource.FromVisual(Visual)
    Dim win As System.Windows.Forms.IWin32Window = New OldWindow(source.Handle)
    Return win
End Function

Private Class OldWindow
    Implements System.Windows.Forms.IWin32Window

    Public Sub New(handle As System.IntPtr)
        _handle = handle
    End Sub


    Dim _handle As System.IntPtr
    Public ReadOnly Property Handle As IntPtr Implements Forms.IWin32Window.Handle
        Get

        End Get
    End Property


End Class

End Module

Answer 3

//add a reference to System.Windows.Forms.dll

public partial class MainWindow : Window, System.Windows.Forms.IWin32Window
{
    public MainWindow()
    {
        InitializeComponent();
    }

    private void button_Click(object sender, RoutedEventArgs e)
    {
        var fbd = new FolderBrowserDialog();
        fbd.ShowDialog(this);
    }

    IntPtr System.Windows.Forms.IWin32Window.Handle
    {
        get
        {
            return ((HwndSource)PresentationSource.FromVisual(this)).Handle;
        }
    }
}

Answer 4

If you specify Owner, you will get a Modal dialog over the specified WPF window.

To get WinForms compatible Win32 window create a class implements IWin32Window like this

 public class OldWindow : System.Windows.Forms.IWin32Window
{
    IntPtr _handle;

    public OldWindow(IntPtr handle)
    {
        _handle = handle;
    }

    #region IWin32Window Members

    IntPtr System.Windows.Forms.IWin32Window.Handle
    {
        get { return _handle; }
    }

    #endregion
}

And use an instance of this class at your WinForms

        IntPtr mainWindowPtr = new WindowInteropHelper(this).Handle; // 'this' means WPF Window
        folderBrowserDialog.ShowDialog(new OldWindow(mainWindowPtr));