Arcgis Engine最短路径分析

ArcEngine 最短路径分析（源码）

using System; using ESRI.ArcGIS.Carto; using ESRI.ArcGIS.Geometry; using ESRI.ArcGIS.Geodatabase; using ESRI.ArcGIS.NetworkAnalysis; namespace 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_ipGeometricNetwork.Network;     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);      ipNetFlag.UserClassID = intEdgeUserClassID;      ipNetFlag.UserID = intEdgeUserID;      ipNetFlag.UserSubID = 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_ipGeometricNetwork.Network;    if(m_ipMap!=null)    {     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_ipMap.LayerCount;    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;    else     dblSearchTol = dblHeight / 100;    m_ipPointToEID.SnapTolerance = dblSearchTol;    return true  ;   }   //关闭工作空间              private void CloseWorkspace()   {    m_ipGeometricNetwork = null;    m_ipPoints = 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