Query

[Reghu]

What is the difference between ActiveX Dlls and other Dlls?

Initiative is to success what a lighted match is to a candle...

[Johnny101]

The only difference i know of is the name. When you create an ActiveX dll in VB it compiles into a DLL, used the same, called the same as other dlls. Oh, VB doesnt compile multi-threaded dlls as well as C++ dlls, i think. I've heard of problems with this, but i dont have any first hand experience with this. I think there is some internal structure differences, but i dont think microsoft wants people to know this.

Those are my thoughts on the subject,
John

John Pirkey
MCSD
www.ShallowWaterSystems.com

[Spectre]

An ActiveX dll is an actual dual interface COM server a regular dll is simply a library of functions that can be linked to your program at run-time then called from within your program.

[Johnny101]

Can you elaborate on what you mean by "dual interface"? Do you have references I could look up for some more information?

Thanks,
John

John Pirkey
MCSD
www.ShallowWaterSystems.com

[Spectre]

If you have Visual Studio - Run the MSDN Library for Visual Studio - Select Entire Collection - click the search tab - Type COM in the words to search for - click on Rank (This will sort the list by rank - go to number 78 in the list COM Overview - You may need to know some C++ to really get the full gist of it all. Most COM objects are written in C++ using either ATL or MFC (these are two other topics worth following. They, however can be written (a lot easier IMHO) in Visual Basic (ActiveX dll's and ActiveX exe's). Just keep in mind when reading the material that an ActiveX dll is what they are refering to as an "in-process" server and an ActiveX exe is what they are refering to as a "out-of-process" server.

Hope this helps.

Spectre

[Johnny101]

Thanks! I knew about the IUnknown and IDispatch interfaces, but wasn't clear on their differences and when they were used.

Thanks again,
John

John Pirkey
MCSD
www.ShallowWaterSystems.com