Turn off displays

Display.cs

public static class Display {
    private const uint WmSyscommand = 0x0112;
    private const int ScMonitorpower = 0xF170;
    private const int HwndBroadcast = 0xFFFF;
    private const int ShutOffDisplay = 2;
    
    [DllImport("user32.dll", SetLastError = true)]
    private static extern bool PostMessage(IntPtr hWnd, uint msg, IntPtr wParam, IntPtr lParam);

    public static void TurnOff() {
        PostMessage((IntPtr)HwndBroadcast, WmSyscommand, (IntPtr)ScMonitorpower, (IntPtr)ShutOffDisplay);
    }
}