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Communicating between Module and Class Module

Hi

I have a DLL project that has a module and a class module.
For some reason, I cannot call the class module functions
from the module.

1. Why is this?
2. Any suggested work-arounds?

Reasons for doing this:
I would like the class to raise an event - something I cannot do from
the regular module (right?). Some of the code in the module CANNOT
exist in a class module because it uses the AddressOf function. So
I have to go back and forth between the two with the functionality.

Bob

aeklund

1. You cannot call a function within a class unless you create the object:
dim o as new Class1
o.Function

2. I just did the same thing, here is how I did it..

In your module declare a module level variable of your class: Public m_oClass as Class1

In your class Initialize Event set that public module variable to the same instance of the class:
Private Sub Class1_Initialize()
Set m_oClass = Me
End Sub

In your class Terminate Event set that public module variable to nothing to clean up the resources
Private Sub Class1_Terminate()
Set m_oClass = Nothing
End Sub

Now, the call... In your module you can now call any public property, sub, function in your class: Call m_oClass1.Function

To hide the sub/function from out of process application, declare it with the Friend keyword: Friend Sub MyFunction()

Hope that helps...

aeklund

Here is a working example of the above:

'module code:
Option Explicit

Public m_oObject As Class1

Public Sub CallBackFunction()
Call m_oObject.DoSomething
End Sub

'class code: (name=Class1)
Option Explicit

Private Sub Class_Initialize()
Set m_oObject = Me
End Sub

Private Sub Class_Terminate()
Set m_oObject = Nothing
End Sub

Friend Sub DoSomething()
Msgbox "It worked!"
End Sub

BobsExEx

ASKER

Interesting idea. I have already put in what you said and it is similar to your later message.

However, everytime I try to run it (by starting the app, then switching to another app so that a WM Message comes through), the entire IDE crashes without a message or anything.

When I comment out the call to the class sub, then the IDE doesn't crash (even keeping all declarations and "set"s the same). I have error handling in there but it doesn't even get to that point.

BobsExEx

ASKER

ASKER CERTIFIED SOLUTION

aeklund

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BobsExEx

ASKER

aeklund

Yeah, I had replaced the msgbox with a debug.print just in case.

I am going to play around with it some more and I will get back to you.

BobsExEx

ASKER

You get the prize, bro.

I appreciate your work on this so I threw an extra 250 pts on. I don't think I would have figured that out.

It still runs with some instability but I think it has to do with my running in the IDE and breaking out before messages are processed correctly.

Thanks

BobsExEx

ASKER

oh - I can't add award more than 500 per question...

Thanks again.

BobsExEx

ASKER

Very nice. Tough stuff.

Bob

aeklund

Glad to help. Thanks for the points... I was stuck on a similar problem and took me some time to figure it out, but this is how I did it and it works like a charm.