Hope I have the correct bulletin board and hope someone can help me.

I have to re-write a VB ActiveX dll in C++ and amoungst other things,
copy its interface.  It currently interfaces with a Visual Basic
client.  Needless to say there is no useful documentation on the
current implementation available to me and I am not a Visual Basic
programmer.

Can anyone tell me the correct way to declare a C++ ActiveX dll in
Visual Basic so that I can test my dll's API?

The current VB test client (testing the VB ActiveX dll) includes the
code:

(General) (Declaration) section

Dim MyObject as aXObj   'name of ActiveX dll

then in the 3 API sub-routines:

Private Sub Command1_Click()
Set anObject = aXObj
...
anObject.APIFunctionCall

The variable 'anObject' is never explicitly declared.

Is that declaration and use correct and can I copy it for C++?

NB
On initialisation the dll performs operations which only need to be
performed once, loading some .ini file settings.  I do not want to
have the dll re-initialised each time a call to one of the API
functions is made.

Thanks,

You can work those out from running up a simple test App

\_ this creates a new instance in MyObject
     and may destroy the old instance in MyObject

Set anObject = aXObj
will simply make  anObject  point to whatever is in aXObj
- which in this case is illegal as aXObj is a Class not an instance of
a Class

Better do:  Set MyObject = New aXObj
just once - in some sort of initialization routine
and Set MyObject = Nothing when you want to destroy the Object

Out of interest, does it _have_ to be an AX DLL ?

It is much easier to write 'real' DLLs and 'front' them with a VB
Class - instances can be referred to using Handles that the 'real' DLL
can feed back to VB

IMO the only reasons for writing AX DLLs in another language than VB
is when the thing is an OCX with a visual interface, or it is going to
raise events in say a Form or a Class