Browse DevX
Sign up for e-mail newsletters from DevX

Tip of the Day
Language: Enterprise
Expertise: Beginner
Aug 3, 1999



Building the Right Environment to Support AI, Machine Learning and Deep Learning

Use IDispatchImpl for Default Implementation for IDispatch of Dual Interfaces

The communication between the COM client and server can happen in three ways: the vtble interface, dispinterface, or dual interface. The COM client can communicate with the server through IDispatch interface by calling the member functions in IDispatch interface to indirectly invoke the functions in the automation server. DispInterface (or dispatch interface) is implemented by IDispatch and are distinct from COM interfaces (vtable interfaces). Actually, the set of functions implemented by IDispatch :: invoke is called a dispinterface. A dual interface is a dispinterface that makes all the functions that are available through invoke also available through vtbl.

IDispatchImpl provides a default implementation for the IDispatch portion of any dual interface on your object. A dual interface derives from IDispatch (instead of IUnknown ) and uses only Automation-compatible types. Like a dispinterface, a dual interface supports early and late binding; however, a dual interface differs in that it also supports vtble binding.

Jai Bardhan
Comment and Contribute






(Maximum characters: 1200). You have 1200 characters left.



Thanks for your registration, follow us on our social networks to keep up-to-date