Re: Diff between interface, IDispatch interface and dispinterface

From:
"Alexander Nickolov" <agnickolov@mvps.org>
Newsgroups:
microsoft.public.vc.atl
Date:
Mon, 8 May 2006 12:43:47 -0700
Message-ID:
<uNB65etcGHA.3900@TK2MSFTNGP05.phx.gbl>
IDispatch is a COM interface. It's the representation of all
dispinterfaces in the COM world. A dispinterface is a specific
contract how to implement IDispatch. It is not a COM interface,
and is represented in the COM world via IDispatch. In COM
terms all dispinterfaces are derived from IDispatch with no
extra methods, e.g. they are all identical to IDispatch (in COM
terms only of course). There's a special breed, the so called
dual interfaces, that marry the two - a dual interface is derived
from IDispatch and has extra methods, and these same methods
are also available as the dispinterface implemented for that
particular IDispatch instance. Dual interfaces have significant
limitations both in the COM world and in the Automation world
and are often inappropriate. That said, however, in certain cases
they are indispensible.

--
=====================================
Alexander Nickolov
Microsoft MVP [VC], MCSD
email: agnickolov@mvps.org
MVP VC FAQ: http://www.mvps.org/vcfaq
=====================================

"Radde" <msradder@gmail.com> wrote in message
news:1147066900.310638.71780@u72g2000cwu.googlegroups.com...

Hello,
Can anyone tell me whats the difference between IDispatch interface
and dispinterface..
When to use what???

Regards

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