VB Decompiler Hosted by TheAutomaters.com     Memberlist   VB6 Controls - Dual Interface Mechanism      VB Decompiler Forum Index -> Structures Author Message Dr Memory Expert Joined: 16 Aug 2004 Posts: 147 Location: Surrey, UK Posted: Wed Sep 15, 2004 4:54 pm     Post subject: VB6 Controls - Dual Interface Mechanism I've just stumbled into a large cave inside the runtime library, can't see very clearly but it appears to be an engine room for the VB class library dual-interface support mechanism ... ... is there much known/recorded about this system? ... does anybody know COM internals??? I understand what dual-interface is, but that's about it ... my COM is still conversational, not fluent! (in case reader is unaware, dual interface allows a COM object to be accessed via both VTable and IDispatch systems - "early-binding" and "late-binding" in other words - this system is used for private classes like forms and controls, that's why intrinsic control methods are very fast, not much more expensive than Function call) _________________ [size=75:2sg2dqh1]At first, I was irridescent. Then, I became transparent. Finally, I was absent ... Back to top Dr Memory Expert Joined: 16 Aug 2004 Posts: 147 Location: Surrey, UK Posted: Wed Sep 15, 2004 6:27 pm     Post subject: Ahh... there is ALWAYS something new to learn from Bruce McKinney ("Hardcore Visual Basic", on your MSDN CD) Code: So if COM servers with dual interfaces are better than those with IDispatch interfaces, where do you find dual interfaces? The answer is: almost everywhere. For example, you’ll always get them from Visual Basic. In fact, there are only two development tools I know of that create dispatch-only ActiveX components. Unfortunately, one of them is probably the most common tool for creating components: the Microsoft Foundation Class (MFC) library. The other is Delphi (version 2). Both Microsoft and Borland are moving to new tools that create dual interfaces. That was written 93-95, I guess, MFC would be legacy now, isn't it? Anyhow, the way MSVBVM60 implements dual interfacing is really neat - there is no single way to do this, btw, it's a technique not a COM option, .. and what the VB guys came up with looks pretty cool to me! _________________ [size=75:2sg2dqh1]At first, I was irridescent. Then, I became transparent. Finally, I was absent ... Back to top    VB Decompiler Forum Index -> Structures All times are GMT Page 1 of 1   You can post new topics in this forum You can reply to topics in this forum You can edit your posts in this forum You can delete your posts in this forum You can vote in polls in this forum Powered by phpBB © 2001, 2005 phpBB Group