public PowerRequest(string simpleReason)
        {
            // Set up the diagnostic string.
            POWER_REQUEST_CONTEXT context;
            context.Version = POWER_REQUEST_CONTEXT_VERSION;
            context.Flags = POWER_REQUEST_CONTEXT_SIMPLE_STRING;
            context.SimpleReasonString = simpleReason;

            // Create the request and get a handle.
            powerRequestHandle = PowerCreateRequest(ref context);
            if (powerRequestHandle.IsInvalid)
            {
                throw new Win32Exception();
            }
        }
 private static extern bool PowerClearRequest(
     SafePowerRequestHandle hPowerRequest, PowerRequestType RequestType);