//C# private void axMapControl1_OnMouseDown(object sender, IMapControlEvents2_OnMouseDownEvent e) { if (e.button == 2) { IRubberBand rubberband = new RubberCircleClass(); IGeometry geometry = rubberband.TrackNew(this.axMapControl1.ActiveView.ScreenDisplay, null); CreateCircleElement(geometry, this.axMapControl1.Map); this.axMapControl1.ActiveView.PartialRefresh(esriViewDrawPhase.esriViewGraphics, null, null); } } private void CreateCircleElement(IGeometry geometry, IMap map) { ISegment segment = geometry as ISegment; ISegmentCollection polygon = new PolygonClass(); object Missing = Type.Missing; polygon.AddSegment(segment, ref Missing, ref Missing); IElement element = new CircleElement(); element.Geometry = polygon as IGeometry; IGraphicsContainer graphicsContainer = map as IGraphicsContainer; graphicsContainer.AddElement(element, 0); }