internal void FirePropertyValueChangedEvent(PropertyValueChangedEventArgs e)
 {
     PropertyValueChangedEventHandler del = OnPropertyValueChanged;
     if (del != null) del(this, e);
 }
 public int OnPropertyValueChanged(string DeviceId, PropertyKey key)
 {
     PropertyValueChangedEventArgs arg = new PropertyValueChangedEventArgs(DeviceId, key);
     _DeviceEnumerator.FirePropertyValueChangedEvent(arg);
     return 0;
 }