protected void Page_Load(object sender, EventArgs e)
        {
            if (!Page.IsPostBack)
            {
                InMemoryFeatureLayer inmemoryFeatureLayer = new InMemoryFeatureLayer();
                inmemoryFeatureLayer.ZoomLevelSet.ZoomLevel01.DefaultPointStyle.PointType = PointType.Bitmap;
                inmemoryFeatureLayer.ZoomLevelSet.ZoomLevel01.DefaultPointStyle = PointStyles.Capital1;
                inmemoryFeatureLayer.ZoomLevelSet.ZoomLevel01.ApplyUntilZoomLevel = ApplyUntilZoomLevel.Level20;
                Random ra = new Random();
                for (int i = 0; i < 20000; i++)
                {
                    int x = ra.Next(0, 1800);
                    int y = ra.Next(0, 900);
                    double dx = x / 10;
                    double dy = y / 10;
                    PointShape point = new PointShape(dx, dy);
                    Feature fe = new Feature(dx, dy);
                    inmemoryFeatureLayer.InternalFeatures.Add(fe);
                }
                inmemoryFeatureLayer.BuildIndex();
                LayerOverlay overLay = new LayerOverlay();
  
                overLay.Layers.Add("inmemoryFeatureLayer",inmemoryFeatureLayer);

                inmemoryFeatureLayer.Open();
                Map1.CurrentExtent = inmemoryFeatureLayer.GetBoundingBox();
                inmemoryFeatureLayer.Close();

                Map1.MapUnit = GeographyUnit.DecimalDegree;
                Map1.CustomOverlays.Add(overLay);

                
            }
        }
       

        protected void Map1_Click1(object sender, MapClickedEventArgs e)
        {
            InMemoryFeatureLayer inmLayer = (Map1.CustomOverlays[0] as LayerOverlay).Layers["inmemoryFeatureLayer"] as InMemoryFeatureLayer;
            inmLayer.Open();
            Feature clickedFeature = inmLayer.FeatureSource.GetFeaturesNearestTo(new PointShape(e.Position.X, e.Position.Y), GeographyUnit.DecimalDegree, 1, ReturningColumnsType.NoColumns)[0];
        }