Top 15 BCS Object Model Classes

Applies to: SharePoint Server 2010

To develop rich solutions that use external data, you can program with the interfaces and types provided by the Microsoft Business Connectivity Services (BCS) object model. This topic lists some of the most important interfaces and types in the BCS object model and explains a few scenarios in which they will be most useful. For information about all the types and interfaces in the BCS object model, see Business Connectivity Services Class Library.

See Business Connectivity Services Object Model Code Snippets for some sample code snippets that use these interfaces and types.

Commonly Used Types and Interfaces in the BCS Object Model

Type or Interface


Microsoft.BusinessData.MetadataModel. IMetadataCatalog

The entry point into the BDC object model. Use the DatabaseBasedMetadataCatalog on the server, FileBackedMetadataCatalog on both client and server, and RemoteSharedFileBackedMetadataCatalog on the client.

Microsoft.BusinessData.MetadataModel. ILobSystem

Contains the details about an external system.

Microsoft.BusinessData.MetadataModel. IEntity

An external content type in the BDC Metadata Store.

Microsoft.BusinessData.MetadataModel. IMethod

An operation that can be performed on the external content type.

Microsoft.BusinessData.Runtime. IEntityInstance

An entity instance (also known as external item) is a single item returned from an external system in BDC. The IEntityInstance interface abstracts the underlying data sources and insulates the clients from having to learn application-specific coding paradigms; it enables them to access all business data in a single, simplified way. By using the IEntityInstance interface, you can work with a row of data from a database in just the same way as working with a complex .NET Framework structure returned by a Web service.An entity instance in BDC has special semantics attached to it. For example, it has the ability to know which field or fields in the row represent the identifier for the entity instance and enables to you call methods such as GetAssociated, GetIdentifierValues, and Execute on that entity instance.

Microsoft.BusinessData.Runtime. IEntityInstanceEnumerator

Enumerators can be used to read the data in the external items collection, but they cannot be used to modify the underlying collection. IEntityInstanceEnumerator supports streaming and is therefore very useful when the back-end application returns great amounts of data.

Microsoft.BusinessData.Runtime. IFilter

Enables you to get filtered entity instances from the external system.


The entry point to a BDC Model in the BDC Administration object model.


Enables you to create and modify LobSystems in the BDC Metadata Store.


Enables you to create and modify external content types in the BDC Metadata Store.


Enables you to create and modify operations for external content types in the BDC Metadata Store.


Enables you to describe the fields of external content types in the BDC Metadata Store.


The entry point to the BCS client cache on the client.


The entry point into the BCS client offlining object model used for syncing data.


The public object model to package and deploy a declarative solution in Outlook. The Visual Studio 2008 with Visual Studio Tools for Office package produced will be for a Visual Studio 2008 with Visual Studio Tools for OfficeOutlook add-in.