A4WaterUtilities.GeoNetTools.TracePath C# (CSharp) Method

        public static string TracePath(double[] Xs, double[] Ys, string GeoNetName, IApplication app, IMap map, bool traceIndeterminate,
                                   double snapTol, bool selectEdges, out IEnumNetEID juncEIDs, out IEnumNetEID edgeEIDs, out IGeometricNetwork gn)
        {
            gn = null;

            juncEIDs = null;
            edgeEIDs = null;

            List<INetFlag> pNetFlags = null;
            IFlagDisplay pFlagDisplay = null;

            IJunctionFlag[] junctionFlags = null;
            IEdgeFlag[] edgeFlags = null;

            ITraceFlowSolverGEN traceFlowSolver = null;

            List<IEdgeFlag> pEdgeFlags = null;
            List<IJunctionFlag> pJunctionFlags = null;
            INetElementBarriers pEdgeElementBarriers;
            INetElementBarriers pJunctionElementBarriers;
            ISelectionSetBarriers pSelectionSetBarriers;
            List<IGeometricNetwork> gnList = null;
            INetworkAnalysisExt pNetAnalysisExt = null;
            UID pID = null;
            try
            {
                gnList = Globals.GetGeometricNetworks(ref map);
                if (gnList == null)
                {
                    MessageBox.Show(A4LGSharedFunctions.Localizer.GetString("GeoNetToolsError_17a"));
                    return "";
                }

                int gnIdx = -1;

                gnIdx = Globals.GetGeometricNetwork(ref gnList, GeoNetName);
                if (gnIdx != -1)
                {
                    gn = (IGeometricNetwork)gnList[gnIdx];
                }

                pNetFlags = new List<INetFlag>();

                //  INetFlag[] netFlags = new INetFlag[Xs.Length];

                for (int i = 0; i < Xs.Length; i++)
                {
                    IPoint snappedPoint = null; int EID = -1;
                    if (gn == null)
                    {

                        pNetFlags.Add(Globals.GetJunctionFlag(Xs[i], Ys[i], ref map, ref gnList, snapTol, ref gnIdx,
                                    out snappedPoint, out EID, out  pFlagDisplay, true) as INetFlag);

                        //Set network to trace
                        if (gnIdx > -1)
                            gn = gnList[gnIdx] as IGeometricNetwork;

                    }
                    else
                    {
                        pNetFlags.Add(Globals.GetJunctionFlagWithGN(Xs[i], Ys[i], ref map, ref gn, ref snapTol, out snappedPoint, out EID, out  pFlagDisplay, true) as INetFlag);

                    }
                }

                if (gn == null || pNetFlags.Count < 1)
                {
                    return (A4LGSharedFunctions.Localizer.GetString("GeoNetToolsError_17b"));

                }

                if (app != null)
                {

                    pID = new UID();

                    pID.Value = "esriEditorExt.UtilityNetworkAnalysisExt";
                    pNetAnalysisExt = (INetworkAnalysisExt)app.FindExtensionByCLSID(pID);
                    Globals.SetCurrentNetwork(ref pNetAnalysisExt, ref gn);
                    traceFlowSolver = Globals.CreateTraceFlowSolverFromToolbar(ref pNetAnalysisExt, out pEdgeFlags, out pJunctionFlags, out pEdgeElementBarriers, out pJunctionElementBarriers, out pSelectionSetBarriers) as ITraceFlowSolverGEN;

                }
                else
                {
                    traceFlowSolver = new TraceFlowSolverClass() as ITraceFlowSolverGEN;
                    INetSolver netSolver = traceFlowSolver as INetSolver;

                    netSolver.SourceNetwork = gn.Network;

                }

                traceFlowSolver.TraceIndeterminateFlow = traceIndeterminate;

                if (pEdgeFlags != null)
                {
                    foreach (IEdgeFlag pEdFl in pEdgeFlags)
                    {
                        pNetFlags.Add((INetFlag)pEdFl);

                    }
                }
                if (pJunctionFlags != null)
                {

                    foreach (IJunctionFlag pJcFl in pJunctionFlags)
                    {
                        pNetFlags.Add((INetFlag)pJcFl);
                    }
                }
                //if (startNetFlag != null)
                //{

                //    pNetFlags.Add((INetFlag)startNetFlag);

                //}

                Globals.AddFlagsToTraceSolver(pNetFlags.ToArray(), ref traceFlowSolver, out junctionFlags, out edgeFlags);
                int intCount = 1;
                System.Object[] segCosts = new System.Object[1];
                segCosts[0] = new System.Object();

                traceFlowSolver.FindPath(esriFlowMethod.esriFMConnected, esriShortestPathObjFn.esriSPObjFnMinMax,
                    out juncEIDs, out edgeEIDs, intCount, ref segCosts);

                //Select junction features
                map.ClearSelection();
                IJunctionFlag[] junctionFlag = null;
                Globals.SelectJunctions(ref map, ref  gn, ref juncEIDs, ref junctionFlag, "", "", "", true);
                if (selectEdges)
                    Globals.SelectEdges(ref map, ref gn, ref edgeEIDs);
                edgeEIDs.Reset();

                //Draw edge graphics
                IEnvelope env = Globals.DrawEdges(ref map, ref gn, ref edgeEIDs);

                return edgeEIDs.Count.ToString();

            }
            catch (Exception Ex)
            {
                MessageBox.Show(A4LGSharedFunctions.Localizer.GetString("GeoNetToolsLbl_17a") + "\n" + Ex.Message);
                return "";

            }
        }