async void CenterlnglatAroundPOISearch()
        {
            ReverseGeocodingOption rgo = new ReverseGeocodingOption();

            rgo.XCoors = new double[] { double.Parse(centerLng.Text) };
            rgo.YCoors = new double[] { double.Parse(centerLat.Text) };
            ReverseGeoCodingResult rgcs = await ReGeoCode.GeoCodeToAddressWithOption(rgo);
            if (rgcs.Erro == null)
            {
                Debug.WriteLine(rgcs);
            }
            else
            {
                Debug.WriteLine(rgcs.Erro.Message);
            }
        }
        private async void ReGeoCodeTest(double lng, double lat)
        {
            ReverseGeocodingOption rgo = new ReverseGeocodingOption();
            rgo.XCoors = new double[] { lng };
            rgo.YCoors = new double[] { lat };
            ReverseGeoCodingResult rgcs = await ReGeoCode.GeoCodeToAddressWithOption(rgo);
            this.Dispatcher.RunAsync(CoreDispatcherPriority.High, () =>
      {
          if (rgcs.Erro == null && rgcs.resultList != null)
          {
              IEnumerable<ReverseGeocodingInfo> reverseGeocodeResult = rgcs.resultList;
              foreach (ReverseGeocodingInfo poi in reverseGeocodeResult)
              {
                  int i = 0;
                  foreach (POI poilist in poi.Pois)
                  {
                      i++;
                      AMarker marker = new AMarker();
                      marker.LngLat = new ALngLat(poilist.X, poilist.Y);
                      ATip tip = new ATip();
                      tip.Title = i + ": " + poilist.Name;
                      tip.ContentText = poilist.Address;
                      marker.TipFrameworkElement = tip;
                      markerList.Add(marker);
                      map.Children.Add(marker);

                  }

              }
              markerList[0].OpenTip();
              map.SetOverlaysFitView();

          }
          else
          {
              MessageDialog msd = new MessageDialog(rgcs.Erro.Message);
              this.Dispatcher.RunAsync(CoreDispatcherPriority.Low, () =>
              {
                  msd.ShowAsync();
              });
          }
      });
        }