Work with network datasets

Starting with 10.9.1, ArcGIS Enterprise SDK provides support for working with network datasets within server object extensions. Developers can use the SDK to create, edit and build network datasets; get information about how a network dataset is configured; query network elements attributes; and make use of a forward star to find connected network elements.

Open a network dataset

There are two ways to access a network dataset through a SOE. One way to do this is to get the network dataset from the current map service’s data source, if the current map service includes a network dataset layer. The following C# example shows how to retrieve the service’s network dataset layer and open the network dataset by accessing the network dataset layer’s data source:

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IMapServer mapServer = pSOH.ServerObject as IMapServer;
IMapServerDataAccess mapServerDataAccess = mapServer as IMapServerDataAccess;
IMapServerInfo mapServerInfo = mapServer.GetServerInfo(mapServer.DefaultMapName);
IMapLayerInfos layerInfos = mapServerInfo.MapLayerInfos;
IMapLayerInfo ndLayerInfo = null;

// Get the network dataset layer from current service
for (var i = 0; i < layerInfos.Count; i++)
{
  IMapLayerInfo layerInfo = layerInfos.Element[i];
  if (layerInfo.Type.Equals("Network Dataset Layer", StringComparison.InvariantCultureIgnoreCase))
  {
    ndLayerInfo = layerInfo;
    break;
  }
}

// Get the network dataset
if (ndLayerInfo != null)
{
  var dt = mapServerDataAccess.GetDataSource(mapServer.DefaultMapName, ndLayerInfo.ID);
  // Cast the dataset to required network dataset interface
  networkDataset = dt as INetworkDataset;
}

Alternatively, if you know where the network dataset locates on the server, you can retrieve it using the following method:

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IWorkspaceFactory workspaceFactory =
  Activator.CreateInstance(typeof(FileGDBWorkspaceFactoryClass)) as IWorkspaceFactory;
// fgdbPath is the catalog path of the file geodatabase that contains network dataset.
IFeatureWorkspace fWorkspace =
  workspaceFactory.OpenFromFile(fgdbPath, 0) as IFeatureWorkspace;
// fdName is the feature dataset name within the file geodatabase that contains network dataset.
IFeatureDatasetExtensionContainer fdExtensionContainer =
  fWorkspace.OpenFeatureDataset(fdName) as IFeatureDatasetExtensionContainer;
IDatasetContainer2 datasetContainer2 =
  fdExtensionContainer.FindExtension(esriDatasetType.esriDTNetworkDataset) as IDatasetContainer2;
// ndName is the network dataset name.
INetworkDataset networkDataset =
  datasetContainer2.DatasetByName[esriDatasetType.esriDTNetworkDataset, ndName] as INetworkDataset;

Walk through the main network dataset interfaces and classes

As shown above, the first step is to get the network dataset. Once this is done, here are ways to access the desired network dataset interfaces:

• Query the elements of the network dataset

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  INetworkQuery networkQuery = networkDataset as INetworkQuery;

• Query information about adjacent elements in the network dataset

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  INetworkForwardStar fStar = networkQuery.CreateForwardStar();
  INetworkForwardStarAdjacencies fStarAdj = networkQuery.CreateForwardStarAdjacencies();

• Get network dataset configuration information

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  IDatasetComponent datasetComponent = networkDataset as IDatasetComponent;
  IDENetworkDataset deNetworkDataset = datasetComponent.DataElement as IDENetworkDataset;

Create network dataset

There are interfaces to create network dataset programmatically, but it is recommended to use Create Network Dataset From Template tool in a geoprocessing service to create a network dataset, since creating network dataset could potentially take a long time and might not be good for a synchronous service.