How to render a WPF UserControl to a bitmap without creating a window

Question

How can I render a WPF UserControl to a bitmap without creating a window? I need to render a WPF UserControl and upload it to another program. The bitmaps will be rendered t

Answer 1

Based on IDWMaster's solution I did it a bit differently using the System.Windows.Forms.UserControl. Otherwise the bindings were not up-to-date when the export to bitmap happened. This works for me (this is the WPF control to render):

System.Windows.Forms.UserControl controlContainer = new System.Windows.Forms.UserControl();
controlContainer.Width = width;
controlContainer.Height = height;
controlContainer.Load += delegate(object sender, EventArgs e)
{
    this.Dispatcher.BeginInvoke((Action)delegate
    {
        using (FileStream fs = new FileStream(path, FileMode.Create))
        {
            RenderTargetBitmap bmp = new RenderTargetBitmap(width, height, 96, 96, PixelFormats.Pbgra32);
            bmp.Render(this);
            BitmapEncoder encoder = new PngBitmapEncoder();
            encoder.Frames.Add(BitmapFrame.Create(bmp));
            encoder.Save(fs);
            controlContainer.Dispose();
        }
    }, DispatcherPriority.Background);
};

controlContainer.Controls.Add(new ElementHost() { Child = this, Dock = System.Windows.Forms.DockStyle.Fill });
IntPtr handle = controlContainer.Handle;