ArcObjects Library Reference (GeoDatabase)

NetworkForwardStar Class

A container for querying information about adjacent elements in the network dataset.

NetworkForwardStar is a non-creatable object. References to non-creatable objects must be obtained through other objects.

Product Availability

Available with ArcGIS Engine, ArcGIS Desktop, and ArcGIS Server.

Description

For a given network junction element and, optionally, incoming edge elements in a network dataset, the NetworkForwardStar object efficiently queries adjacent network elements and their attribute values. This query can be performed repeatedly using the NetworkForwardStar on the adjacent elements returned by previous queries, allowing one to traverse throughout the network to perform a network analysis.

The NetworkForwardStar is not merely the object through which to retrieve adjacency information from the elements of a network dataset. While this is indeed part of its intended usage, the network dataset itself already provides a raw, unfiltered view of all of the data stored within the dataset (including all elements' raw attribute and adjacency information). Therefore, clients of the network dataset can retrieve adjacency information and attribute data directly from the elements themselves, without the need for any intermediate objects. The true purpose of the NetworkForwardStar component is to provide an automatically-filtered, problem-specific view of this raw information to be used by client algorithms of the network dataset (e.g., which restrictions, U-turn policies, attribute adjustments, etc. to honor during network adjacency traversal).

Extended Error Information

Use the ISupportErrorInfo method InterfaceSupportsErrorInfo to determine if the object supports extended error information. If the object supports extended error info, VC++ developers should use the OLE/COM IErrorInfo interface to access the ErrorInfo object. Visual Basic developers should use the global error object Err to retrieve this extended error information.

Interfaces

Interfaces	Description
INetworkForwardStar	Provides access to members that query information about adjacent elements in the network dataset.
INetworkForwardStarEx	Provides access to members that specify the configuration for this NetworkForwardStar object and query information about adjacent elements in the network dataset.
INetworkForwardStarSetup	Provides access to members that specify the configuration for this NetworkForwardStar object.
ISupportErrorInfo	Indicates whether a specific interface can return Automation error objects.

Remarks

The NetworkForwardStar object is created by calling the INetworkQuery::CreateForwardStar method on the network dataset. This method can only be called when a Network license is checked out.