最短路径分析（源码）using System; ArcEngine using ESRI.ArcGIS.Carto;using ESRI.ArcGIS.Geometry;using ESRI.ArcGIS.Geodatabase;using workAnalysis;//12namespace GisEditor{/// <summary>/// 最短路径分析/// </summary>public class ClsPathFinder{private IGeometricNetwork m_ipGeometricNetwork;private IMap m_ipMap;private IPointCollection m_ipPoints;private IPointToEID m_ipPointToEID;private double m_dblPathCost =0;private IEnumNetEID m_ipEnumNetEID_Junctions;private IEnumNetEID m_ipEnumNetEID_Edges;private IPolyline m_ipPolyline;#region Public Function//返回和设置当前地图public IMap SetOrGetMap{set{ m_ipMap = value;}get{return m_ipMap;}}//打开几何数据集的网络工作空间public void OpenFeatureDatasetNetwork(IFeatureDataset FeatureDataset){CloseWorkspace();if (!InitializeNetworkAndMap(FeatureDataset))Console.WriteLine( "打开network出错");}//输入点的集合public IPointCollection StopPoints{set{m_ipPoints= value;}get{return m_ipPoints;}}//路径成本public double PathCost{get {return m_dblPathCost;}}//返回路径的几何体public IPolyline PathPolyLine(){IEIDInfo ipEIDInfo;IGeometry ipGeometry;if(m_ipPolyline!=null)return m_ipPolyline;m_ipPolyline = new PolylineClass();IGeometryCollection ipNewGeometryColl = m_ipPolyline as IGeometryCollection;ISpatialReference ipSpatialReference = m_ipMap.SpatialReference; IEIDHelper ipEIDHelper = new EIDHelperClass();ipEIDHelper.GeometricNetwork = m_ipGeometricNetwork;ipEIDHelper.OutputSpatialReference = ipSpatialReference;ipEIDHelper.ReturnGeometries = true;IEnumEIDInfo ipEnumEIDInfo =ipEIDHelper.CreateEnumEIDInfo(m_ipEnumNetEID_Edges);int count = ipEnumEIDInfo.Count;ipEnumEIDInfo.Reset();for(int i =0;i<count;i++){ipEIDInfo = ipEnumEIDInfo.Next();ipGeometry = ipEIDInfo.Geometry;ipNewGeometryColl.AddGeometryCollection( ipGeometry as IGeometryCollection);}return m_ipPolyline;}//解决路径public void SolvePath(string WeightName){try{int intEdgeUserClassID;int intEdgeUserID;int intEdgeUserSubID;int intEdgeID;IPoint ipFoundEdgePoint;double dblEdgePercent;/*PutEdgeOrigins方法的第二个参数要求是IEdgeFlag类型的数组,* 在VB等其他语言的代码中，只需传人该类型数组的第一个元素即* 可，但C#中的机制有所不同，需要作出如下修改：使用* ITraceFlowSolverGEN替代ITraceFlowSolver*/ITraceFlowSolverGEN ipTraceFlowSolver = new TraceFlowSolverClass() as ITraceFlowSolverGEN;INetSolver ipNetSolver = ipTraceFlowSolver as INetSolver;INetwork ipNetwork = m_work;ipNetSolver.SourceNetwork = ipNetwork;INetElements ipNetElements = ipNetwork as INetElements;int intCount = m_ipPoints.PointCount;//定义一个边线旗数组IEdgeFlag[] pEdgeFlagList = new EdgeFlagClass[intCount];for(int i = 0;i<intCount ;i++){INetFlag ipNetFlag = new EdgeFlagClass()as INetFlag;IPoint ipEdgePoint = m_ipPoints.get_Point(i);//查找输入点的最近的边线m_ipPointToEID.GetNearestEdge(ipEdgePoint, out intEdgeID,out ipFoundEdgePoint, out dblEdgePercent);ipNetElements.QueryIDs( intEdgeID, esriElementType.esriETEdge, out intEdgeUserClassID, out intEdgeUserID,out intEdgeUserSubID);erClassID = intEdgeUserClassID;erID = intEdgeUserID;erSubID = intEdgeUserSubID;IEdgeFlag pTemp = (IEdgeFlag)(ipNetFlag as IEdgeFlag);pEdgeFlagList[i]=pTemp;}ipTraceFlowSolver.PutEdgeOrigins(ref pEdgeFlagList);INetSchema ipNetSchema = ipNetwork as INetSchema;INetWeight ipNetWeight =ipNetSchema.get_WeightByName(WeightName);INetSolverWeights ipNetSolverWeights = ipTraceFlowSolver as INetSolverWeights;ipNetSolverWeights.FromToEdgeWeight = ipNetWeight;//开始边线的权重ipNetSolverWeights.ToFromEdgeWeight = ipNetWeight;//终止边线的权重object [] vaRes =new object[intCount-1];//通过findpath得到边线和交汇点的集合ipTraceFlowSolver.FindPath(esriFlowMethod.esriFMConnected,esriShortestPathObjFn.esriSPObjFnMinSum,out m_ipEnumNetEID_Junctions,out m_ipEnumNetEID_Edges,intCount-1, ref vaRes);//计算元素成本m_dblPathCost = 0;for (int i =0;i<vaRes.Length;i++){double m_Va =(double) vaRes[i];m_dblPathCost = m_dblPathCost + m_Va;}m_ipPolyline = null;}catch(Exception ex){Console.WriteLine(ex.Message);}}#endregion#region Private Function//初始化几何网络和地图private bool InitializeNetworkAndMap(IFeatureDataset FeatureDataset) {IFeatureClassContainer ipFeatureClassContainer;IFeatureClass ipFeatureClass ;IGeoDataset ipGeoDataset;ILayer ipLayer ;IFeatureLayer ipFeatureLayer;IEnvelope ipEnvelope, ipMaxEnvelope ;double dblSearchTol;INetworkCollection ipNetworkCollection = FeatureDataset as INetworkCollection;int count = ipNetworkCollection.GeometricNetworkCount;//获取第一个几何网络工作空间m_ipGeometricNetwork = ipNetworkCollection.get_GeometricNetwork(0); INetwork ipNetwork = m_work;{m_ipMap = new MapClass();ipFeatureClassContainer = m_ipGeometricNetwork as IFeatureClassContainer;count = ipFeatureClassContainer.ClassCount;for(int i =0;i<count;i++){ipFeatureClass = ipFeatureClassContainer.get_Class(i); ipFeatureLayer = new FeatureLayerClass();ipFeatureLayer.FeatureClass = ipFeatureClass;m_ipMap.AddLayer( ipFeatureLayer);}}count = m_yerCount;ipMaxEnvelope = new EnvelopeClass();for(int i =0;i<count;i++){ipLayer = m_ipMap.get_Layer(i);ipFeatureLayer = ipLayer as IFeatureLayer;ipGeoDataset = ipFeatureLayer as IGeoDataset;ipEnvelope = ipGeoDataset.Extent;ipMaxEnvelope.Union( ipEnvelope);}m_ipPointToEID = new PointToEIDClass();m_ipPointToEID.SourceMap = m_ipMap;m_ipPointToEID.GeometricNetwork = m_ipGeometricNetwork;double dblWidth = ipMaxEnvelope.Width;double dblHeight = ipMaxEnvelope.Height;if( dblWidth > dblHeight)dblSearchTol = dblWidth / 100;elsedblSearchTol = dblHeight / 100;m_ipPointToEID.SnapTolerance = dblSearchTol;return true ;}//关闭工作空间private void CloseWorkspace(){m_ipGeometricNetwork = null;m_ipPointToEID = null;m_ipEnumNetEID_Junctions = null;m_ipEnumNetEID_Edges = null;m_ipPolyline = null;}#endregion}}备注：在调用该类时的次序：ClsPathFinder m_ipPathFinder;if(m_ipPathFinder==null)//打开几何网络工作空间{m_ipPathFinder = new ClsPathFinder();ipMap = this.m_ActiveView.FocusMap;ipLayer = ipMap.get_Layer(0);ipFeatureLayer = ipLayer as IFeatureLayer;ipFDB = ipFeatureLayer.FeatureClass.FeatureDataset;m_ipPathFinder.SetOrGetMap = ipMap;m_ipPathFinder.OpenFeatureDatasetNetwork(ipFDB);}private void ViewMap_OnMouseDown(object sender,ESRI.ArcGIS.MapControl.IMapControlEvents2_OnMouseDownEvent e)//获取地图上鼠标输入的点{IPoint ipNew ;if( m_ipPoints==null){m_ipPoints = new MultipointClass();m_ipPathFinder.StopPoints = m_ipPoints;}ipNew =ViewMap.ActiveView.ScreenDisplay.DisplayTransformation.ToMapPoint(e.x ,e.y);object o = Type.Missing;m_ipPoints.AddPoint(ipNew,ref o,ref o);}m_ipPathFinder.SolvePath("Weight");//先解析路径IPolyline ipPolyResult = m_ipPathFinder.PathPolyLine();//最后返回最短路径。