One of the important capabilities of C# is being able to interoperate with existing code, whether it is COM-based or in a native DLL. This chapter provides a brief overview of how interop works.
For more information on interop, check out COM and .NET Interoperability by Andrew Troelsen (Apress, 2002).
Interop with COM objects is a very complex subject; COM and .NET have different—and sometimes incompatible—object models and execution environments.
If you want to use an existing COM object and you can stay within the simple COM interfaces, it is generally fairly straightforward to perform most functions. To call ...