🚀 go-pugleaf

Hello, everyone! I am migrating my program from C++ Builder 5 to version 6.
The platform is ADO/COM+. Problem about VARIANT puzzles me. I tried to
create a simple server program. I created a ActiveX Library, and then a
Transaction Data Module, and then compiled then program, it's Ok. But when
any ADO component was added into the data module, the compiler reported an
error 'Ambiguity between 'ITransaction' and 'OleDb::ITransaction'. Actually
it's a conflict between header files. I had to modified the header file
'comsvcs.h' shipped with C++ Builder, insert '::' prior ITransaction
declaration, and then I could compile it. But, another problem emerge, the
results of codes below were different!

A:
Variant v = "abc";

B:
Variant A;
v = "abc";

Value of variable v in form A was empty, while value in form B were 'abc'.
What's wrong?!
Maybe I shouldn't modify the source file shipped by the manufacturer. But
how can I use ADO and COM+ at the same time?!

Another problem is, I am using *VARIANT in type library method to return
value to client. In C++ Builder 5, VARIANT in type library is converted to
TVariant in the codes generated automatically. While in C++Builder 6, it's
converted to VARIANT instead. I found that the server couldn't receive the
value sent by the client in parameter *VARIANT, and the value modified by
the server can't be got by the client. I set the parameter to be 'in/out' in
the type library. My program works smoothly in C++ Builder 6. What's wrong
in it?

Any comment from you are appreciated!

Thanks!
Mountain