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   var env = e.Graphic.Geometry as Envelope;    Polygon p = new Polygon() { SpatialReference = env.SpatialReference };    PointCollection ring = new PointCollection();    ring.Add(new MapPoint(env.XMin, env.YMin));    ring.Add(new MapPoint(env.XMin, env.YMax));    ring.Add(new MapPoint(env.XMax, env.YMax));    ring.Add(new MapPoint(env.XMax, env.YMin));    ring.Add(new MapPoint(env.XMin, env.YMin));    p.Rings.Add(ring);    e.Graphic.Geometry = p;   var env = e.Graphic.Geometry as Envelope;    Polygon p = new Polygon() { SpatialReference = env.SpatialReference };    PointCollection ring = new PointCollection();    ring.Add(new MapPoint(env.XMin, env.YMin));    ring.Add(new MapPoint(env.XMin, env.YMax));    ring.Add(new MapPoint(env.XMax, env.YMax));    ring.Add(new MapPoint(env.XMax, env.YMin));    ring.Add(new MapPoint(env.XMin, env.YMin));    p.Rings.Add(ring);    e.Graphic.Geometry = p;