Article Discussion: Your First COM Client In Visual C++

Your First COM Client In Visual C++ If you have any questions or comments about this article then please post them here.

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Hi,

This article was very good for me, but I don't how can I pass a string to VB. Your code doesn't show it.

I ' m trying something like this :

IN C++:

{
_bstr_t pato (L"gato");

pJBMenu->Insert_Description (pato);
}

IN VB DLL (class Menu):

Public Function Insert_Description(ByVal desc As String) As Long
On Error GoTo Fatal
Dim g As String

' Insert a new description in the list
FormStartup.Insert_Description (desc)

Insert_Description = 1
Exit Function
Fatal:

MsgBox "ERRO " & Err.Description & " " & desc
End Function

The C++ program compiles, but breaks in this moment :

pJBMenu->Insert_Description (pato);

Could someone help me ?

Thanks,

Joao Araujo

First a question:- where are the support files located?

Secondly, I found a bunch of small mistakes which you might like to
correct:

GetDlgItemText(IDC_CARDNO,cardtype);
should read
GetDlgItemText(IDC_CARDTYPE,cardtype);

ValidateCard (num As String , type As String) As Long
should read
ValidateCard (ByVal num As String , ByVal cardtype As String) As Long
otherwise VC++ thinks that the function expects unsigned shorts instead
of BSTRs and also type is a reserved word

using namespace Validate
should read
using namespace ValidateCard;