private void UpdateThumb()
{
if (Thumb != IntPtr.Zero)
{
DwmQueryThumbnailSourceSize(Thumb, out PSIZE size);
DWM_THUMBNAIL_PROPERTIES props = new DWM_THUMBNAIL_PROPERTIES
{
fVisible = true,
dwFlags = DWM_TNP_VISIBLE | DWM_TNP_RECTDESTINATION | DWM_TNP_OPACITY,
//opacity = (byte)opacity.Value,
opacity = 255,
rcDestination = new Rect(ThumbnailControl.Left, ThumbnailControl.Top, ThumbnailControl.Right, ThumbnailControl.Bottom)
};
if (size.x < ThumbnailControl.Width)
{
props.rcDestination.Right = props.rcDestination.Left + size.x;
}
if (size.y < ThumbnailControl.Height)
{
props.rcDestination.Bottom = props.rcDestination.Top + size.y;
}
DwmUpdateThumbnailProperties(Thumb, ref props);
}
}
static extern int DwmUpdateThumbnailProperties(IntPtr hThumb, ref DWM_THUMBNAIL_PROPERTIES props);