Building a .NET Connectivity Assembly

You’ve seen how to connect to a business system using SharePoint Designer. The wizards make it simple to connect to SQL Server databases or appropriately designed WCF services. But what happens if you want to connect to something a bit more exotic? The answer is to create a .NET connectivity assembly. By creating a connectivity assembly, you can write code to handle any of the operation stereotypes supported by the BDC service. As mentioned earlier, BDC itself doesn’t read or write to the external data store; it simply delegates to an appropriate endpoint. By creating a connectivity assembly, you can effectively create custom endpoints to do whatever is appropriate for your application.

Pluggable Connector Framework

As briefly covered earlier in the section “Connector Framework,” BCS makes connections to external systems via a pluggable connector framework. It is therefore possible to create custom connectors to interface with external systems. While creating custom connectors is beyond the scope of this chapter, it’s worthwhile for you to know the differences between creating a custom connector and using a connectivity assembly.