Chapter Twelve. Migration and Interop Strategies

So far in this book, I have explained most of the nuts and bolts of COM interoperability and given you an introduction to the .NET Framework. What I have not discussed is when to use COM interoperability. In other words, when does it make sense to use COM Interop to call your existing COM components from a .NET client, and when does it make more sense just to rewrite the component as a managed component? In this chapter, I discuss these issues and show you how to develop an overall strategy for migrating your existing unmanaged code to .NET. I define the notion of horizontal and vertical migration and discuss how you can determine which approach is best for your software.