c#+AE开发一些常用到的方法

 public class ArcengineUtil

    {

  //将距离转换函数
        public static double ConvertPixelsToMapUnits(IActiveView pActiveView, double pixelUnits)
        {
            IPoint p1 = pActiveView.ScreenDisplay.DisplayTransformation.VisibleBounds.UpperLeft;
            IPoint p2 = pActiveView.ScreenDisplay.DisplayTransformation.VisibleBounds.UpperRight;
            int x1, x2, y1, y2;
            pActiveView.ScreenDisplay.DisplayTransformation.FromMapPoint(p1, out x1, out y1);
            pActiveView.ScreenDisplay.DisplayTransformation.FromMapPoint(p2, out x2, out y2);
            double pixelExtent = x2 - x1;
            double realWorldDisplayExtent = pActiveView.ScreenDisplay.DisplayTransformation.VisibleBounds.Width;
            double sizeOfOnePixel = realWorldDisplayExtent / pixelExtent;


            return pixelUnits * sizeOfOnePixel;
        }



        /// 将距离转换函数
        public static double ConvertPixelToMapUnit(IActiveView pActiveView, double pixelUnits)
        {
            double realWorldDisplayExtent;
            int pixelExtent;
            double sizeOfOnePixel;
            pixelExtent = pActiveView.ScreenDisplay.DisplayTransformation.get_DeviceFrame().right
                - pActiveView.ScreenDisplay.DisplayTransformation.get_DeviceFrame().left;

            realWorldDisplayExtent = pActiveView.ScreenDisplay.DisplayTransformation.VisibleBounds.Width;
            sizeOfOnePixel = realWorldDisplayExtent / pixelExtent;
            return pixelUnits * sizeOfOnePixel;
        }

     /// <summary>
        /// 获取一个图层中所有的地物
        /// </summary>
        /// <param name="featureClass"></param>
        /// <returns></returns>
        public static List<IFeature> GetLayerFeatures(IFeatureClass featureClass)
        {
            List<IFeature> result = new List<IFeature>();
            if (featureClass == null)
                return result;
            IFeatureCursor featureCursor = featureClass.Search(null, false);
            IFeature feature = featureCursor.NextFeature();
            while (feature != null)
            {
                result.Add(feature);
                feature = featureCursor.NextFeature();
            }
            ESRI.ArcGIS.ADF.ComReleaser.ReleaseCOMObject(featureCursor);
            return result;
        }

 /// <summary>
        /// 根据字段名获取地物的值
        /// </summary>
        /// <param name="feature"></param>
        /// <param name="fieldName"></param>
        /// <returns></returns>
        public static string GetFieldValue(IFeature feature, string fieldName)
        {
            //根据字段名，获取字段的索引位置
            int indexField = feature.Fields.FindField(fieldName);
            if (indexField == -1)
                return "";
            return feature.get_Value(indexField).ToString();
        }

    /// <summary>
        /// 获取线性地物的长度
        /// </summary>
        /// <param name="feature"></param>
        /// <returns></returns>
        public static double GetLineFeatureLength(IFeature feature)
        {
            if (feature.Shape.GeometryType != esriGeometryType.esriGeometryPolyline)
                return 0;
            else
            {
                IPolyline polyline = feature.Shape as IPolyline;
                return polyline.Length;
            }
        }


        public static IRgbColor GetRGB(int red, int green, int blue)
        {
            IRgbColor rGBColor = new RgbColorClass();
            rGBColor.Red = red;
            rGBColor.Green = green;
            rGBColor.Blue = blue;
            return rGBColor;
        }

  #region  闪烁地物
        /// <summary>
        /// 闪烁地物
        /// </summary>
        /// <param name="mapControl"></param>
        /// <param name="iFeature"></param>
        /// <param name="iMap"></param>
        public static void FlashFeature(AxMapControl mapControl, IFeature iFeature)
        {


            IActiveView iActiveView = mapControl.ActiveView;
            if (iActiveView != null)
            {
                iActiveView.ScreenDisplay.StartDrawing(0, (short)esriScreenCache.esriNoScreenCache);
                //根据几何类型调用不同的过程 
                switch (iFeature.Shape.GeometryType)
                {
                    case esriGeometryType.esriGeometryPolyline:
                        FlashLine(mapControl, iActiveView.ScreenDisplay, iFeature.Shape);
                        break;
                    case esriGeometryType.esriGeometryPolygon:
                        FlashPolygon(mapControl, iActiveView.ScreenDisplay, iFeature.Shape);
                        break;
                    case esriGeometryType.esriGeometryPoint:
                        FlashPoint(mapControl, iActiveView.ScreenDisplay, iFeature.Shape);
                        break;
                    default:
                        break;
                }
                iActiveView.ScreenDisplay.FinishDrawing();
            }
        }


        //闪烁线 
        public static void FlashLine(AxMapControl mapControl, IScreenDisplay iScreenDisplay, IGeometry iGeometry)
        {
            ISimpleLineSymbol iLineSymbol;
            ISymbol iSymbol;
            IRgbColor iRgbColor;


            iLineSymbol = new SimpleLineSymbol();
            iLineSymbol.Width = 4;
            iRgbColor = new RgbColor();
            iRgbColor.Red = 255;
            iLineSymbol.Color = iRgbColor;
            iSymbol = (ISymbol)iLineSymbol;
            iSymbol.ROP2 = esriRasterOpCode.esriROPNotXOrPen;
            mapControl.FlashShape(iGeometry, 3, 200, iSymbol);
        }


        //闪烁面 
        public static void FlashPolygon(AxMapControl mapControl, IScreenDisplay iScreenDisplay, IGeometry iGeometry)
        {
            ISimpleFillSymbol iFillSymbol;
            ISymbol iSymbol;
            IRgbColor iRgbColor;


            iFillSymbol = new SimpleFillSymbol();
            iFillSymbol.Style = esriSimpleFillStyle.esriSFSSolid;
            iFillSymbol.Outline.Width = 12;


            iRgbColor = new RgbColor();
            iRgbColor.RGB = System.Drawing.Color.FromArgb(100, 180, 180).ToArgb();
            iFillSymbol.Color = iRgbColor;


            iSymbol = (ISymbol)iFillSymbol;
            iSymbol.ROP2 = esriRasterOpCode.esriROPNotXOrPen;
            iScreenDisplay.SetSymbol(iSymbol);
            mapControl.FlashShape(iGeometry, 3, 200, iSymbol);
        }


        //闪烁点 
        public static void FlashPoint(AxMapControl mapControl, IScreenDisplay iScreenDisplay, IGeometry iGeometry)
        {
            ISimpleMarkerSymbol iMarkerSymbol;
            ISymbol iSymbol;
            IRgbColor iRgbColor;


            iMarkerSymbol = new SimpleMarkerSymbol();
            iMarkerSymbol.Style = esriSimpleMarkerStyle.esriSMSCircle;
            iRgbColor = new RgbColor();
            iRgbColor.RGB = System.Drawing.Color.FromArgb(0, 0, 0).ToArgb();
            iMarkerSymbol.Color = iRgbColor;
            iSymbol = (ISymbol)iMarkerSymbol;
            iSymbol.ROP2 = esriRasterOpCode.esriROPNotXOrPen;
            mapControl.FlashShape(iGeometry, 3, 200, iSymbol);
        }
        #endregion

 /// <summary>
        /// 闪烁地物
        /// </summary>
        /// <param name="mapCtrl"></param>
        /// <param name="flashGeometry"></param>
        public static void FlashGeometry(AxMapControl mapCtrl, IGeometry flashGeometry)
        {
            //通过IHookActions闪烁要素集合 
            HookHelperClass m_pHookHelper = new HookHelperClass();
            m_pHookHelper.Hook = mapCtrl.Object;
            IHookActions hookActions = (IHookActions)m_pHookHelper;
            hookActions.DoAction(flashGeometry, esriHookActions.esriHookActionsFlash);
            Application.DoEvents();
            m_pHookHelper.ActiveView.ScreenDisplay.UpdateWindow();
        }

 /// <summary>
        /// 定位
        /// </summary>
        /// <param name="geometry">要定位的地物</param>
        public static void LocateFeature(IGeometry geometry,AxMapControl Axmap)
        {
            if (geometry == null) return;
            if (geometry.GeometryType == esriGeometryType.esriGeometryPoint)
            {
                Axmap.CenterAt(geometry as IPoint);
            }
            else
            {
                Axmap.Extent = geometry.Envelope;
            }
        }

    /// <summary>
        /// 获取两个地物相交的部分
        /// </summary>
        /// <param name="geo1">相交的第一个地物</param>
        /// <param name="geo2">相交的第二个地物</param>
        /// <returns></returns>
        public static IGeometry GetDifferenceGeo(IGeometry geo1, IGeometry geo2)
        {
            ITopologicalOperator topo = geo2 as ITopologicalOperator;
            return topo.Difference(geo1);
        }


        public static List<IFeature> GetCurrentLyrSelectedFeatures(IMap map,esriGeometryType geoType)
        {


            IFeature pFeature = null;
            List<IFeature> features = new List<IFeature>();
            ISelection selection = map.FeatureSelection;
            IEnumFeature pEnumFeature = selection as IEnumFeature;
            pFeature = pEnumFeature.Next();
            while (pFeature != null)
            {
                if (pFeature.Shape.GeometryType == geoType)
                {
                    features.Add(pFeature);
                }
               pFeature= pEnumFeature.Next();
            }
            return features;
        }

   }