public static extern int DwmExtendFrameIntoClientArea(IntPtr hwnd, ref MARGINS pMarInset);
static void wnd_Loaded(object sender, RoutedEventArgs e)
{
Window wnd = (Window)sender;
Brush originalBackground = wnd.Background;
wnd.Background = Brushes.Transparent;
try
{
IntPtr mainWindowPtr = new WindowInteropHelper(wnd).Handle;
HwndSource mainWindowSrc = HwndSource.FromHwnd(mainWindowPtr);
mainWindowSrc.CompositionTarget.BackgroundColor = Color.FromArgb(0, 0, 0, 0);
//System.Drawing.Graphics desktop = System.Drawing.Graphics.FromHwnd(mainWindowPtr);
//float DesktopDpiX = desktop.DpiX;
//float DesktopDpiY = desktop.DpiY;
MARGINS margins = new MARGINS();
margins.cxLeftWidth = -1;
margins.cxRightWidth = -1;
margins.cyTopHeight = -1;
margins.cyBottomHeight = -1;
DwmExtendFrameIntoClientArea(mainWindowSrc.Handle, ref margins);
}
catch (DllNotFoundException)
{
wnd.Background = originalBackground;
}
}
public static extern int DwmExtendFrameIntoClientArea(IntPtr hwnd, ref MARGINS pMarInset);