Is there a way to check to see if another program is running full screen.

Question

Just like the question says. Can I see if someone else, program, is running full screen?

Full screen means that the entire screen is obscured, possibly running in a different video mode than the desktop.

Answer 1

Here is some code that does it. You want to take care about the multi screen case, especially with applications like Powerpoint

    [StructLayout(LayoutKind.Sequential)]
    private struct RECT
    {
        public int left;
        public int top;
        public int right;
        public int bottom;
    }

    [DllImport("user32.dll")]
    private static extern bool GetWindowRect(HandleRef hWnd, [In, Out] ref RECT rect);

    [DllImport("user32.dll")]
    private static extern IntPtr GetForegroundWindow();

    public static bool IsForegroundFullScreen()
    {
        return IsForegroundFullScreen(null);
    }

    public static bool IsForegroundFullScreen(Screen screen)
    {
        if (screen == null)
        {
            screen = Screen.PrimaryScreen;
        }
        RECT rect = new RECT();
        GetWindowRect(new HandleRef(null, GetForegroundWindow()), ref rect);
        return new Rectangle(rect.left, rect.top, rect.right - rect.left, rect.bottom - rect.top).Contains(screen.Bounds); 
    }