VectorLayer vl;
        Random rnd = new Random();
        VectorPlacemark current = null;
        Point offset = new Point();
        int idx = 1;
        public Marks()
        {
            InitializeComponent();
            Tag = "Marks";
            vl = new VectorLayer();
            maps.Layers.Add(vl);
            maps.MouseLeftButtonUp += new MouseButtonEventHandler(maps_MouseLeftButtonUp);
            for (int i = 0; i < 10; i++)
            {
                // create random coordinates
                Point pt = new Point(-80 + rnd.Next(160), -80 + rnd.Next(160));
                AddMark(pt);
            }
        }
        void maps_MouseLeftButtonUp(object sender, MouseButtonEventArgs e)
        {
            if (Keyboard.Modifiers == ModifierKeys.Control)
            {
                AddMark(maps.ScreenToGeographic(e.GetPosition(maps)));
            }
        }
        void mark_MouseLeftButtonDown(object sender, MouseButtonEventArgs e)
        {
            VectorPlacemark pm = (VectorPlacemark)sender;
            if (Keyboard.Modifiers == ModifierKeys.Shift)
            {
                e.Handled = true;
                if (pm.CaptureMouse())
                {
                    current = pm;
                    offset = e.GetPosition(current);
                }
            }
            else if (Keyboard.Modifiers == ModifierKeys.Alt)
            {
                e.Handled = true;
                vl.Children.Remove(pm);
            }
        }
        void AddMark(Point pt)
        {
            Color clr = Utils.GetRandomColor(128, 192);
            VectorPlacemark mark = new VectorPlacemark()
            {
                GeoPoint = pt,
                Label = new TextBlock()
                {
                    RenderTransform = new TranslateTransform() { Y = -5 },
                    IsHitTestVisible = false,
                    Text = idx.ToString()
                },
                LabelPosition = LabelPosition.Top,
                Geometry = Utils.CreateBaloon(),
                Stroke = new SolidColorBrush(Colors.DarkGray),
                Fill = new SolidColorBrush(clr),
            };
            mark.MouseLeftButtonDown += new MouseButtonEventHandler(mark_MouseLeftButtonDown);
            mark.MouseLeftButtonUp += new MouseButtonEventHandler(mark_MouseLeftButtonUp);
            mark.MouseMove += new MouseEventHandler(mark_MouseMove);
            vl.Children.Add(mark);
            vl.LabelVisibility = LabelVisibility.Visible;
            idx++;
        }
        void mark_MouseMove(object sender, MouseEventArgs e)
        {
            if (current != null)
            {
                Point pt = e.GetPosition(maps);
                pt.X -= offset.X; pt.Y -= offset.Y;
                current.GeoPoint = maps.ScreenToGeographic(pt);
            }
        }
        void mark_MouseLeftButtonUp(object sender, MouseButtonEventArgs e)
        {
            VectorPlacemark pm = (VectorPlacemark)sender;
            if (pm != null)
                pm.ReleaseMouseCapture();
            current = null;
        }

public class Utils
  {
    public static Geometry CreateBaloon()
    {
      PathGeometry pg = new PathGeometry();
      pg.Transform = new TranslateTransform() { X = -10, Y = -24.14 };
      PathFigure pf = new PathFigure() { StartPoint = new Point(10, 24.14), IsFilled = true, IsClosed = true };
      pf.Segments.Add(new ArcSegment() { SweepDirection = SweepDirection.Counterclockwise, Point = new Point(5, 19.14), RotationAngle = 45, Size = new Size(10, 10) });
      pf.Segments.Add(new ArcSegment() { SweepDirection = SweepDirection.Clockwise, Point = new Point(15, 19.14), RotationAngle = 270, Size = new Size(10, 10), IsLargeArc = true });
      pf.Segments.Add(new ArcSegment() { SweepDirection = SweepDirection.Counterclockwise, Point = new Point(10, 24.14), RotationAngle = 45, Size = new Size(10, 10) });
      pg.Figures.Add(pf);
      return pg;
    }
    public static void LoadShapeFromResource(VectorLayer vl, string resname, string dbfname, Location location, bool clear, ProcessShapeItem pv)
    {
        using (Stream shapeStream = Assembly.GetExecutingAssembly().GetManifestResourceStream(resname))
        {
            using (Stream dbfStream = Assembly.GetExecutingAssembly().GetManifestResourceStream(dbfname))
            {
                if (shapeStream != null)
                {
                    if (clear)
                        vl.Children.Clear();
                    vl.LoadShape(shapeStream, dbfStream, location, true, pv);
                }
            }
        }
    }
   
    public static void LoadKMZFromResources(VectorLayer vl, string resname, bool clear, ProcessVectorItem pv)
    {
      using (Stream zipStream = Assembly.GetExecutingAssembly().GetManifestResourceStream(resname))
      {
        if (zipStream != null)
        {
          if( clear)
            vl.Children.Clear();
          vl.LoadKMZ(zipStream, true, pv);
        }
      }
    }
    public static void LoadKMLFromResources(VectorLayer vl, string resname, bool clear, ProcessVectorItem pv)
    {
        using (Stream stream = Assembly.GetExecutingAssembly().GetManifestResourceStream(resname))
        {
            if (stream != null)
            {
                if (clear)
                    vl.Children.Clear();
                vl.LoadKML(stream, false, pv);
            }
        }
    }
    static Random rnd = new Random();
    public static Color GetRandomColor(byte a)
    {
      return Color.FromArgb(a, (byte)rnd.Next(255), (byte)rnd.Next(255), (byte)rnd.Next(255));
    }
    public static Color GetRandomColor(byte min, byte a)
    {
      return Color.FromArgb(a, (byte)( min + rnd.Next(255-min)),
        (byte)(min + rnd.Next(255-min)), (byte)(min + rnd.Next(255-min)));
    }
  }