Marshaling Data with COM Interop

COM interop provides support for both using COM objects from managed code and exposing managed objects to COM. Support for marshaling data to and from COM is extensive and almost always provides the correct marshaling behavior.

The Microsoft .NET Framework SDK includes the following COM interop tools:

• Type Library Importer (Tlbimp.exe), which converts a COM type library to an interop assembly. From this assembly, the interop marshaling service generates wrappers that perform data marshaling between managed and unmanaged memory.
• Type Library Exporter (Tlbexp.exe), which produces a COM type library from an assembly and generates a wrapper that performs marshaling during method calls.

This section describes the processes for customizing interop wrappers when you can (or must) supply the marshaler with additional type information.

In This Section

• COM Data Types
  Provides corresponding managed and unmanaged data types.
• Customizing COM Callable Wrappers
  Describes how to explicitly marshal data types using the MarshalAsAttribute attribute at design time.
• Customizing Runtime Callable Wrappers
  Describes how to adjust the marshaling behavior of types in an interop assembly and how to define COM types manually.

Related Topics

• Advanced COM Interop
  Describes COM interop concepts and conversion rules.
• Assembly to Type Library Conversion Summary
  Describes the assembly to type library export conversion process.
• Type Library to Assembly Conversion Summary
  Describes the type library to assembly import conversion process.