public static bool ExtendGlassFrame(Window window, Thickness margin) { if (!DwmIsCompositionEnabled()) return false; IntPtr hwnd = new WindowInteropHelper(window).Handle; if (hwnd == IntPtr.Zero) throw new InvalidOperationException("The window must be shown before extending glass."); // Set the background to transparent from both the WPF and Win32 perspectives window.Background = Brushes.Transparent; HwndSource.FromHwnd(hwnd).CompositionTarget.BackgroundColor = Colors.Transparent; MARGINS margins = new MARGINS(margin); DwmExtendFrameIntoClientArea(hwnd, ref margins); return true; }
static extern void DwmExtendFrameIntoClientArea(IntPtr hwnd, ref MARGINS margins);