I am designing an n-tier Windows application by using .NET Framework 4, VS2010, and SQL Server 2008. The application will replace an existing client/server application. The existing application was created by using Microsoft Visual Basic 6.0 and consists of a series of COM components that access a SQL Server database. I plan to move the existing COM components into a WCF tier.
I ensure that the COM components can be replaced without impacting the existing user interface (UI) tier. I also need to ensure that the COM components can be replaced separately.
I believe the way to do this is create a common assembly of the new application interface with the COM components. Should this be done on the UI tier or the WCF tier?
Could you please have a look at articles below about migrating COM components to the .NET Framework tier?
Migrating COM/DCOM Applications in Microsoft .NET Framework
Integration and Migration of COM+ services to WCF
I would like to recommend you discuss this type of issue at Windows Communication Foundation (WCF) forum for better assistance.
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