public void Undo()
{
switch (_speedStack.Pop())
{
case FanSpeed.High:
_ceilingFan.High();
break;
case FanSpeed.Medium:
_ceilingFan.Medium();
break;
case FanSpeed.Low:
_ceilingFan.Low();
break;
case FanSpeed.Off:
_ceilingFan.Off();
break;
default:
throw new ArgumentOutOfRangeException();
}
}
public void Execute()
{
_speedStack.Push(_ceilingFan.GetSpeed());
_ceilingFan.Low();
}