BasicCensusMap.MainPage._candidateListBox_SelectionChanged C# (CSharp) Метод

        void _candidateListBox_SelectionChanged(object sender, SelectionChangedEventArgs e)
        {
            int index = (sender as ListBox).SelectedIndex;
            if (index >= 0)
            {
                MapPoint candidatePoint = _candidateGraphicsLayer.Graphics[index].Geometry as MapPoint;
                double displaySize = MyMap.MinimumResolution * 30000;

                ESRI.ArcGIS.Client.Geometry.Envelope displayExtent = new ESRI.ArcGIS.Client.Geometry.Envelope(
                    candidatePoint.X - (displaySize / 2),
                    candidatePoint.Y - (displaySize / 2),
                    candidatePoint.X + (displaySize / 2),
                    candidatePoint.Y + (displaySize / 2));

                MyMap.ZoomTo(displayExtent);
            }
        }