修鍊九陰真經Windows Phone開發 (17)：Tip與技巧2

如果需要準確定位的位置，裝置每移動100米就進行資料更新，可以這樣寫：

GeoCoordinateWatcher watcher = new GeoCoordinateWatcher(GeoPositionAccuracy.Hight);
watcher.MovementThreshold =100;
watcher.PositionChanged += new EventHandler<GeoPositionChangedEventArgs<GeoCoordinate>>(watcher_PositionChanged);
watcher.Start();

private void watcher_PositionChanged(object sender , GeoPositionChangedEventArgs<GeoCoordinate> e)
{
Deployment.Current.Dispatcher.BiginInvoke( ()=>MyPositionChanged(e));
}

private void MyPositionChanged(GeoPositionChangedEventArgs<GeoCoordinate> e)
{
LongitudeTextBlock.Text = e.Position.Location.Longitude.ToString("0");
LatitudeTextBlock.Text = e.Position.Location.Latitude.ToString("0");
}