VBA object-oriented programming

Question

This question is an extension of a previous question: Return an object in VBA

Now, I'd like to know how to declare and initialize the object in VBA. It seems like I'd do it like so:

Declare Function ConnectMe Lib "C:\Windows\System32\cm.dll" (ByVal Arg1 As String) As ConnectMe
Declare Function login Lib "C:\Windows\System32\cm.dll" (ByVal Arg1 As String, ByVal Arg2 As String) As Boolean

Then, below this line, I could use this code:

dim cm as new ConnectMe

cm.ConnectMe("216.239.51.99")

cm.login("username","password")

However, when I do this, it gives me a "User-defined type not defined" error. How can I declare this C++ class appropriately so that I can create and use an instance in VBA?

Thanks.

Community · Accepted Answer · 2017-05-23 12:19:56Z

2

This code is never going to work as it is. If you want to create a class in C++ under Windows and use it in any other programming language that is not C++, (VB for example) the "normal" approach is to create a COM class or an ActiveX control if you need to draw graphics.

You may also find this answer in SO helpful.

edited May 23, 2017 at 12:19

CommunityBot

11 silver badge

answered Oct 4, 2011 at 17:01

yms

10.4k3 gold badges41 silver badges71 bronze badges

Sign up to request clarification or add additional context in comments.

Comments

Bruno Leite · Accepted Answer · 2011-10-04 16:57:44Z

0

i here again :D

To use this code with your function use:

Dim cm as Object

set cm = ConnectMe("parameter")

if cm.login("username","password") then 
     msgbox "Connect!",vbinformation
else
     msgbox "not connect!",vbinformation
end if

answered Oct 4, 2011 at 16:57

Bruno Leite

1,47713 silver badges17 bronze badges

9 Comments

Sam Youtsey Over a year ago

But how do I declare the function to be available? I'm thinking @yms is correct, that I'm going to need to approach this from an entirely different angle.

Bruno Leite Over a year ago

Sam look this msdn.microsoft.com/en-us/library/bb687915.aspx in this page has same answer.

Sam Youtsey Over a year ago

I found what I believe you're referring to: "[Public | Private] Declare Function name Lib "libname" [Alias "aliasname"] [([arglist])] [As type]" However, when I try to specify the 'ConnectMe' class with "Declare Function ConnectMe Lib "C:\Windows\System32\cm.dll" (ByVal Arg1 As String) As ConnectMe" it complains about the user-defined type. Any suggestions?

Bruno Leite Over a year ago

You registered your DLL with REGSVR32 C:\windows\System32\cm.dll ?

yms Over a year ago

That page does not mention references to classes or objects. As I mentioned in my answer, this problem is not only for C++ to VBA. An instace of a (non-COM) C++ class cannot be used directly in any other programming language.

|

Collectives™ on Stack Overflow

VBA object-oriented programming

2 Answers 2

Comments

9 Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

Comments

9 Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related