C#关闭显示屏，使显示屏处于待机状态

class Program
{
private const uint WM_SYSCOMMAND = 0x112; //系统消息
private const int SC_MONITORPOWER = 0xF170; //关闭显示器的系统命令
private const int MonitorPowerOff = 2; //2为PowerOff, 1为省电状态，-1为开机
private static readonly IntPtr HWND_BROADCAST = new IntPtr(0xffff);//广播消息，所有顶级窗体都会接收

[DllImport("user32.dll")]
private static extern IntPtr SendMessage(IntPtr hWnd, uint Msg, int wParam, int lParam);
static void Main(string[] args)
{
SendMessage(HWND_BROADCAST, WM_SYSCOMMAND, SC_MONITORPOWER, MonitorPowerOff);
}

}