Hello everyone,


I find that we can use tlbexp command like *tlbexp <dll name>* to export tlb
file for a C# COM assembly, but can not use it to export tlb file for an
unmanaged C++ COM DLL. Is that correct?

I am wondering how to export tlb file of an unmanaged C++ COM DLL?


thanks in advance,
George

"George" <(E-Mail Removed)> wrote in message news:B334F3B5-E321-4580-BD7E-(E-Mail Removed)...
> Hello everyone,
>
>
> I find that we can use tlbexp command like *tlbexp <dll name>* to export tlb
> file for a C# COM assembly, but can not use it to export tlb file for an
> unmanaged C++ COM DLL. Is that correct?

Correct.

>
> I am wondering how to export tlb file of an unmanaged C++ COM DLL?

Not all COM DLL's have a type library. If one exists, it might be a separate file or it may be embedded as a resource. You can find
out by using Oleview. Click on "File", "View Typelib..." and opening the DLL.

Brian

Thanks Brian,


When using OLEView to open the native unmanaged COM DLL, there is an error
message.

LoadTypeLib (c:\temp\foo.dll) failed.

Error loading type library/DLL.

TYPE_E_CANTLOADLIBRARY ($80029C4A)

Do you know what is wrong?


regards,
George

"Brian Muth" wrote:

>
> "George" <(E-Mail Removed)> wrote in message news:B334F3B5-E321-4580-BD7E-(E-Mail Removed)...
> > Hello everyone,
> >
> >
> > I find that we can use tlbexp command like *tlbexp <dll name>* to export tlb
> > file for a C# COM assembly, but can not use it to export tlb file for an
> > unmanaged C++ COM DLL. Is that correct?
>
> Correct.
>
> >
> > I am wondering how to export tlb file of an unmanaged C++ COM DLL?
>
> Not all COM DLL's have a type library. If one exists, it might be a separate file or it may be embedded as a resource. You can find
> out by using Oleview. Click on "File", "View Typelib..." and opening the DLL.
>
> Brian
>
>
>

"George" <(E-Mail Removed)> wrote in message
news:7D44BE94-6CB1-4A7B-8DDF-(E-Mail Removed)...
> Thanks Brian,
>
>
> When using OLEView to open the native unmanaged COM DLL, there is an error
> message.
>
> LoadTypeLib (c:\temp\foo.dll) failed.
>
> Error loading type library/DLL.
>
> TYPE_E_CANTLOADLIBRARY ($80029C4A)
>
> Do you know what is wrong?

Looks like the type library is not embedded in the DLL. To verify, open the
DLL in Visual Studio's resource editor, if there are any type libraries they
will show up as custom resources of class "TYPELIB".


>
>
> regards,
> George
>
> "Brian Muth" wrote:
>
>>
>> "George" <(E-Mail Removed)> wrote in message
>> news:B334F3B5-E321-4580-BD7E-(E-Mail Removed)...
>> > Hello everyone,
>> >
>> >
>> > I find that we can use tlbexp command like *tlbexp <dll name>* to
>> > export tlb
>> > file for a C# COM assembly, but can not use it to export tlb file for
>> > an
>> > unmanaged C++ COM DLL. Is that correct?
>>
>> Correct.
>>
>> >
>> > I am wondering how to export tlb file of an unmanaged C++ COM DLL?
>>
>> Not all COM DLL's have a type library. If one exists, it might be a
>> separate file or it may be embedded as a resource. You can find
>> out by using Oleview. Click on "File", "View Typelib..." and opening the
>> DLL.
>>
>> Brian
>>
>>
>>

Thanks Ben,


I have followed your approach and I think there is no typelib embedded in
the DLL. I am not using ATL and MFC, and developing unmanaged native C++ COM
DLL from scratch.

In my situation, how to generate type library? I am using Visual Studio 2005.


regards,
George

"Ben Voigt [C++ MVP]" wrote:

>
> "George" <(E-Mail Removed)> wrote in message
> news:7D44BE94-6CB1-4A7B-8DDF-(E-Mail Removed)...
> > Thanks Brian,
> >
> >
> > When using OLEView to open the native unmanaged COM DLL, there is an error
> > message.
> >
> > LoadTypeLib (c:\temp\foo.dll) failed.
> >
> > Error loading type library/DLL.
> >
> > TYPE_E_CANTLOADLIBRARY ($80029C4A)
> >
> > Do you know what is wrong?
>
> Looks like the type library is not embedded in the DLL. To verify, open the
> DLL in Visual Studio's resource editor, if there are any type libraries they
> will show up as custom resources of class "TYPELIB".
>
>
> >
> >
> > regards,
> > George
> >
> > "Brian Muth" wrote:
> >
> >>
> >> "George" <(E-Mail Removed)> wrote in message
> >> news:B334F3B5-E321-4580-BD7E-(E-Mail Removed)...
> >> > Hello everyone,
> >> >
> >> >
> >> > I find that we can use tlbexp command like *tlbexp <dll name>* to
> >> > export tlb
> >> > file for a C# COM assembly, but can not use it to export tlb file for
> >> > an
> >> > unmanaged C++ COM DLL. Is that correct?
> >>
> >> Correct.
> >>
> >> >
> >> > I am wondering how to export tlb file of an unmanaged C++ COM DLL?
> >>
> >> Not all COM DLL's have a type library. If one exists, it might be a
> >> separate file or it may be embedded as a resource. You can find
> >> out by using Oleview. Click on "File", "View Typelib..." and opening the
> >> DLL.
> >>
> >> Brian
> >>
> >>
> >>
>
>
>

George wrote:
> Thanks Ben,
>
>
> I have followed your approach and I think there is no typelib
> embedded in the DLL. I am not using ATL and MFC, and developing
> unmanaged native C++ COM DLL from scratch.
>
> In my situation, how to generate type library? I am using Visual
> Studio 2005.

You have to build a type library using the MIDL compiler. You can then
embed that type library as a resource, or keep it as a separate file.

-cd

Hi George,

> I have followed your approach and I think there is no typelib embedded in
> the DLL. I am not using ATL and MFC, and developing unmanaged native C++
> COM
> DLL from scratch.

Do you use an idl file to specify your library, coclasses and interfaces?
If yes, that idl must be compiled with midl.exe which will create the type
library.

> In my situation, how to generate type library? I am using Visual Studio
> 2005.

If you are using Visual Studio, why don't you use ATL and its wizards for
creating COM objects?

--
SvenC

Thanks cd,


I think I should use MIDL compiler and use the COM DLL as input to generate
type lib, right?

Do you have any reference materials about how to use MIDL compiler to
generate type lib and embedded it into COM DLL?


regards,
George

"Carl Daniel [VC++ MVP]" wrote:

> George wrote:
> > Thanks Ben,
> >
> >
> > I have followed your approach and I think there is no typelib
> > embedded in the DLL. I am not using ATL and MFC, and developing
> > unmanaged native C++ COM DLL from scratch.
> >
> > In my situation, how to generate type library? I am using Visual
> > Studio 2005.
>
> You have to build a type library using the MIDL compiler. You can then
> embed that type library as a resource, or keep it as a separate file.
>
> -cd
>
>
>

Thanks SvenC,


I am using Visual Studio 2005 and I can not find any idl file in the project
directory. Could you let me know how to generate type lib through MIDL
compiler please?

BTW: for some legacy reasons to maintain some code, I can not use ATL or MFC.


regards,
George

"SvenC" wrote:

> Hi George,
>
> > I have followed your approach and I think there is no typelib embedded in
> > the DLL. I am not using ATL and MFC, and developing unmanaged native C++
> > COM
> > DLL from scratch.
>
> Do you use an idl file to specify your library, coclasses and interfaces?
> If yes, that idl must be compiled with midl.exe which will create the type
> library.
>
> > In my situation, how to generate type library? I am using Visual Studio
> > 2005.
>
> If you are using Visual Studio, why don't you use ATL and its wizards for
> creating COM objects?
>
> --
> SvenC
>

Hi George,

> I am using Visual Studio 2005 and I can not find any idl file in the
> project
> directory. Could you let me know how to generate type lib through MIDL
> compiler please?
>
> BTW: for some legacy reasons to maintain some code, I can not use ATL or
> MFC.

You could create an ATL test project which does create an idl and will also
create/configure the necessary midl compiler settings. That should help you
to build the necessary idl for your legacy project.

You will find information about IDL files and the midl compiler in the MSDN.

--
SvenC