学步园

        /// <summary>
        /// 在MapControl上画多边形、面
        /// </summary>
        /// <param name="activeView"></param>
        public void DrawPolygon(ESRI.ArcGIS.Carto.IActiveView activeView)
        {
            if (activeView == null)
            {
                return;
            }

            ESRI.ArcGIS.Display.IScreenDisplay screenDisplay = activeView.ScreenDisplay;

            // Constant
            screenDisplay.StartDrawing(screenDisplay.hDC, (System.Int16)ESRI.ArcGIS.Display.esriScreenCache.esriNoScreenCache); // Explicit Cast
            ESRI.ArcGIS.Display.IRgbColor rgbColor = new ESRI.ArcGIS.Display.RgbColorClass();
            rgbColor.Red = 255;

            ESRI.ArcGIS.Display.IColor color = rgbColor; // Implicit Cast
            ESRI.ArcGIS.Display.ISimpleFillSymbol simpleFillSymbol = new ESRI.ArcGIS.Display.SimpleFillSymbolClass();
            simpleFillSymbol.Color = color;

            ESRI.ArcGIS.Display.ISymbol symbol = simpleFillSymbol as ESRI.ArcGIS.Display.ISymbol; // Dynamic Cast
          //ESRI.ArcGIS.Display.IRubberBand rubberBand = new ESRI.ArcGIS.Display.RubberPolygonClass(); //多边形
            ESRI.ArcGIS.Display.IRubberBand rubberBand = new ESRI.ArcGIS.Display.RubberLineClass(); //折线

            ESRI.ArcGIS.Geometry.IGeometry geometry = rubberBand.TrackNew(screenDisplay, symbol);
            screenDisplay.SetSymbol(symbol);
          //screenDisplay.DrawPolygon(geometry);多边形
            screenDisplay.DrawPolyline(geometry);
            screenDisplay.FinishDrawing();
        }

        private void axMapControl1_OnMouseDown(object sender, ESRI.ArcGIS.Controls.IMapControlEvents2_OnMouseDownEvent e)
        {
            DrawPolygon(this.axMapControl1.ActiveView);
        }