static extern bool FlashWindowEx(ref FLASHWINFO pwfi);
public void FlashTaskBar(FlashOption flashOption)
{
FLASHWINFO fi = new FLASHWINFO();
fi.cbSize = (uint)System.Runtime.InteropServices.Marshal.SizeOf(fi);
fi.hwnd = Process.GetCurrentProcess().MainWindowHandle;
fi.dwFlags = flashOption;
fi.uCount = 1;
fi.dwTimeout = 0;
FlashWindowEx(ref fi);
}