How do you show a Winforms dialog from a WPF window?

The inverse of this question has been answered a number of times.

public static void SetOwner(object activeWindow, object dialog)
{
    if (IsWindow(dialog) && IsWindow(activeWindow))
    {
        (dialog as Window).Owner = (activeWindow as Window);
    }
    else if (IsForm(dialog) && IsForm(activeWindow))
    {
        (dialog as Form).Owner = (activeWindow as Form);
    }
    else if (IsWindow(dialog) && IsForm(activeWindow))
    {
        var wih = new WindowInteropHelper(dialog as Window);
        wih.Owner = (activeWindow as Form).Handle;
    }
    else if (IsForm(dialog) && IsWindow(activeWindow开发者_开发技巧))
    {
        var dialogForm = dialog as Form;
        var ownerWindow = activeWindow as Window;
        // What goes here?
    }           
}

To expand upon SLaks' answer, here is an example such class:

public class WpfWindowWrapper : System.Windows.Forms.IWin32Window
{
    public WpfWindowWrapper(System.Windows.Window wpfWindow)
    {
        Handle = new System.Windows.Interop.WindowInteropHelper(wpfWindow).Handle;
    }

    public IntPtr Handle { get; private set; }
}

It could be used like this from a WPF window's code-behind:

var winForm = new MyWinForm();
winForm.ShowDialog(new WpfWindowWrapper(this));

In this way the Winform dialog acts as a proper child of the WPF window, with the correct modal behavior.

You need to create a class that implements the WinForms IWin32Window interface and returns the WPF window's handle (using new WindowInteropHelper(window).Handle), then pass that to the form's ShowDialog.