Interoperability enables you to preserve and take advantage of existing investments in unmanaged code. Code that runs under the control of the common language runtime (CLR) is called managed code, and code that runs outside the CLR is called unmanaged code. COM, COM+, C++ components, ActiveX components, and Microsoft Win32 API are examples of unmanaged code.
The .NET Framework enables interoperability with unmanaged code through platform invoke services, the System.Runtime.InteropServices namespace, C++ interoperability, and COM interoperability (COM interop).
In This Section
Describes methods to interoperate between C# managed code and unmanaged code.
How to: Access Office Interop Objects by Using Visual C# Features
Describes features that are introduced in Visual C# to facilitate Office programming.
How to: Use Indexed Properties in COM Interop Programming
Describes how to use indexed properties to access COM properties that have parameters.
How to: Use Platform Invoke to Play a Wave File
Describes how to use platform invoke services to play a .wav sound file on the Windows operating system.
Walkthrough: Office Programming
Shows how to create an Excel workbook and a Word document that contains a link to the workbook.
Example COM Class
Demonstrates how to expose a C# class as a COM object.
C# Language Specification
For more information, see the C# Language Specification. The language specification is the definitive source for C# syntax and usage.