private void WpfMap_Loaded(object sender, RoutedEventArgs e)
        {
            WorldMapKitWmsWpfOverlay a = new WorldMapKitWmsWpfOverlay();
            wpfMap1.Overlays.Add(a);

            InMemoryFeatureLayer inmLayer = new InMemoryFeatureLayer();
            inmLayer.InternalFeatures.Add(new Feature("LINESTRING (-20 0, 20 0)"));
            inmLayer.ZoomLevelSet.ZoomLevel01.DefaultLineStyle = LineStyles.Canal1;
            inmLayer.ZoomLevelSet.ZoomLevel01.ApplyUntilZoomLevel = ApplyUntilZoomLevel.Level20;

            LayerOverlay ov = new LayerOverlay();
            ov.Layers.Add(inmLayer);
            wpfMap1.Overlays.Add(ov);



            wpfMap1.MapUnit = GeographyUnit.DecimalDegree;
            wpfMap1.CurrentExtent = new RectangleShape(-133.2515625, 89.2484375, 126.9046875, -88.290625);

            wpfMap1.TrackOverlay.TrackShapeLayer.Open();
            wpfMap1.TrackOverlay.TrackShapeLayer.Columns.Add(new FeatureSourceColumn("Area"));
            wpfMap1.TrackOverlay.TrackShapeLayer.ZoomLevelSet.ZoomLevel01.DefaultTextStyle = TextStyles.CreateSimpleTextStyle("Area", "Arial", 12, DrawingFontStyles.Regular, GeoColor.StandardColors.Black, GeoColor.FromArgb(100, GeoColor.SimpleColors.Green), 2, 0, -8);
            wpfMap1.TrackOverlay.TrackShapeLayer.ZoomLevelSet.ZoomLevel01.ApplyUntilZoomLevel = ApplyUntilZoomLevel.Level20;
            wpfMap1.TrackOverlay.Drawing += new EventHandler<DrawingOverlayEventArgs>(TrackOverlay_Drawing);

            wpfMap1.EditOverlay.EditShapesLayer.Open();
            wpfMap1.EditOverlay.EditShapesLayer.Columns.Add(new FeatureSourceColumn("Area"));
            wpfMap1.EditOverlay.EditShapesLayer.ZoomLevelSet.ZoomLevel01.DefaultTextStyle = TextStyles.CreateSimpleTextStyle("Area", "Arial", 12, DrawingFontStyles.Regular, GeoColor.StandardColors.Black, GeoColor.FromArgb(100, GeoColor.SimpleColors.Green), 2, 0, -8);
            wpfMap1.EditOverlay.EditShapesLayer.ZoomLevelSet.ZoomLevel01.ApplyUntilZoomLevel = ApplyUntilZoomLevel.Level20;

            wpfMap1.EditOverlay.EditsInProcessLayer.DrawingFeatures += new EventHandler<DrawingFeaturesEventArgs>(EditsInProcessLayer_DrawingFeatures);
            wpfMap1.EditOverlay.EditsInProcessLayer.Open();
            wpfMap1.EditOverlay.EditsInProcessLayer.ZoomLevelSet.ZoomLevel01.CustomStyles.Add(TextStyles.CreateSimpleTextStyle("Area", "Arial", 12, DrawingFontStyles.Regular, GeoColor.StandardColors.Black, GeoColor.FromArgb(100, GeoColor.SimpleColors.Green), 2, 0, -8));
            wpfMap1.EditOverlay.EditsInProcessLayer.Close();
            wpfMap1.MapClick += new EventHandler<MapClickWpfMapEventArgs>(wpfMap1_MapClick);
            wpfMap1.Refresh();
        }

        void wpfMap1_MapClick(object sender, MapClickWpfMapEventArgs e)
        {
            System.Diagnostics.Debug.WriteLine(wpfMap1.TrackOverlay.TrackShapeLayer.InternalFeatures[0].GetWellKnownText());
        }

        void EditsInProcessLayer_DrawingFeatures(object sender, DrawingFeaturesEventArgs e)
        {
            if (!wpfMap1.EditOverlay.EditShapesLayer.InternalFeatures[0].ColumnValues.ContainsKey("state"))
            {
                wpfMap1.EditOverlay.EditShapesLayer.InternalFeatures[0].ColumnValues.Add("state", "fillBlankToForbidException");
                PolygonShape polygonShape = wpfMap1.EditOverlay.EditShapesLayer.InternalFeatures[0].GetShape() as PolygonShape;
                wpfMap1.EditOverlay.EditShapesLayer.InternalFeatures[0].ColumnValues["Area"] = polygonShape.GetArea(GeographyUnit.DecimalDegree, AreaUnit.SquareKilometers).ToString();
                e.FeaturesToDraw.Add(wpfMap1.EditOverlay.EditShapesLayer.InternalFeatures[0]);
            }
        }

        private int a = 0;
        void TrackOverlay_Drawing(object sender, DrawingOverlayEventArgs e)
        {
            if (a == 1)
            {
                PolygonShape polygonShape = new PolygonShape(wpfMap1.TrackOverlay.TrackShapeLayer.InternalFeatures[0].GetWellKnownBinary());
                if (polygonShape != null)
                { wpfMap1.TrackOverlay.TrackShapeLayer.InternalFeatures[0].ColumnValues["Area"] = "Area is:" + polygonShape.GetArea(GeographyUnit.DecimalDegree, AreaUnit.SquareKilometers).ToString(); }
            }
                

            else { a++; }
        }

        void EditOverlay_FeatureEdited(object sender, FeatureEditedEditInteractiveOverlayEventArgs e)
        {
            PolygonShape polygonShape = new PolygonShape(wpfMap1.EditOverlay.EditShapesLayer.InternalFeatures[0].GetWellKnownBinary());
            if (polygonShape != null)
            { wpfMap1.EditOverlay.EditShapesLayer.InternalFeatures[0].ColumnValues["Area"] = "Area is:" + polygonShape.GetArea(GeographyUnit.DecimalDegree, AreaUnit.SquareKilometers).ToString(); }
        }