GPIO pins are accessed through the GpioController class defined in the Windows.Devices.Gpio namespace. First, we must check that GPIO is available on the machine. We do this by getting the default controller, and checking whether it's available:

gpio = GpioController.GetDefault(); 
if (gpio != null) 
{ 
   ... 
} 
else 
   Log.Error("Unable to get access to GPIO pin " +
          gpioOutputPin.ToString());