A type library is the Automation standard for describing the objects, properties, and methods exposed by an Automation object. Type libraries provide important benefits.
Another benefit of type libraries is type library marshaling. Type library marshaling allows a custom interface to use the built-in Automation marshaler for the IDispatch interface, thus avoiding the need to build a proxy/stub DLL for the custom interface and then having to register it on each machine the Automation marshaler is automatically available on Windows machines. To use this option, you need only register a type library for the interface on the client machines and restrict the interface to using the Automation compatible data types (see FAQ 34.32). |