创建ServiceArea

/// <summary>
 
        /// Services the area.
 
        /// </summary>
 
        /// <param name="networkDataset">The network dataset.</param>
 
        public void ServiceArea(INetworkDataset networkDataset)
 
        {
 
            log.WriteLog("开始创建ServiceArea...");
 
            IWorkspaceFactory workspaceFactory = new ShapefileWorkspaceFactoryClass();
 
            IWorkspace workspace = workspaceFactory.OpenFromFile(Functions.g_WorkSpacePath, );
 
            IFeatureWorkspace featureWorkspace = workspace as IFeatureWorkspace;
 
            CreateSolverContext(networkDataset);
 
            if (!LoadLocations(featureWorkspace, Functions.g_Hospital))
 
            {
 
                log.WriteLog("LoadLocations失败！");
 
            }
 
            log.WriteLog("ServiceArea创建完成！");
 
        }
 
/// <summary>
 
        /// Geodatabase function: get network dataset
 
        /// </summary>
 
        /// <param name="networkDataset">Input network dataset</param>
 
        /// <returns>DE network dataset</returns>
 
        public IDENetworkDataset GetDENetworkDataset(INetworkDataset networkDataset)
 
        {
 
            // Cast from the network dataset to the DatasetComponent
 
            IDatasetComponent dsComponent = networkDataset as IDatasetComponent;
 
            // Get the data element
 
            return dsComponent.DataElement as IDENetworkDataset;
 
        }
 
        /// <summary>
 
        /// Create NASolver and NAContext
 
        /// </summary>
 
        /// <param name="networkDataset">Input network dataset</param>
 
        private void CreateSolverContext(INetworkDataset networkDataset)
 
        {
 
            if (networkDataset == null) return;
 
            //Get the Data Element
 
            IDENetworkDataset deNDS = GetDENetworkDataset(networkDataset);
 
            INASolver naSolver = new NAServiceAreaSolverClass();
 
            m_NAContext = naSolver.CreateContext(deNDS, naSolver.Name);
 
            ((INAContextEdit)m_NAContext).Bind(networkDataset, new GPMessagesClass());
 
        }
 
/// <summary>
 
        /// Loads the locations.
 
        /// </summary>
 
        /// <param name="featureWorkspace">The feature workspace.</param>
 
        /// <param name="inputFacilities">The input facilities.</param>
 
        /// <returns><c>true</c> if XXXX, <c>false</c> otherwise</returns>
 
        private bool LoadLocations(IFeatureWorkspace featureWorkspace, string inputFacilities)
 
        {
 
            IFeatureClass inputFeatureClass = null;
 
            try
 
            {
 
                inputFeatureClass = featureWorkspace.OpenFeatureClass(inputFacilities);
 
            }
 
            catch (Exception)
 
            {
 
                log.WriteLog("Specified input feature class does not exist");
 
                return false;
 
            }
 
            INamedSet classes = m_NAContext.NAClasses;
 
            INAClass naClass = classes.get_ItemByName("Facilities") as INAClass;
 
            // delete existing locations, except barriers
 
            naClass.DeleteAllRows();
 
            // Create a NAClassLoader and set the snap tolerance (meters unit)
 
            INAClassLoader naClassLoader = new NAClassLoaderClass();
 
            naClassLoader.Locator = m_NAContext.Locator;
 
            ((INALocator3)naClassLoader.Locator).MaxSnapTolerance = ;
 
            naClassLoader.NAClass = naClass;
 
            // Create field map to automatically map fields from input class to NAClass
 
            INAClassFieldMap naClassFieldMap = new NAClassFieldMapClass();
 
            naClassFieldMap.CreateMapping(naClass.ClassDefinition, inputFeatureClass.Fields);
 
            naClassLoader.FieldMap = naClassFieldMap;
 
            // Avoid loading network locations onto non-traversable portions of elements
 
            INALocator3 locator = m_NAContext.Locator as INALocator3;
 
            locator.ExcludeRestrictedElements = true;
 
            locator.CacheRestrictedElements(m_NAContext);
 
            // load network locations
 
            int rowsIn = ;
 
            int rowsLocated = ;
 
            IQueryFilter qf = new QueryFilterClass();
 
            qf.WhereClause = "aaaaaaaaaaa";  
 
            naClassLoader.Load(inputFeatureClass.Search(qf, true) as ICursor, null, ref rowsIn, ref rowsLocated);
 
            if (rowsLocated <= )
 
            {
 
                log.WriteLog("Facilities were not loaded from input feature class");
 
                return false;
 
            }
 
            // Message all of the network analysis agents that the analysis context has changed
 
            INAContextEdit naContextEdit = m_NAContext as INAContextEdit;
 
            naContextEdit.ContextChanged();
 
            return true;
 
        }