I write a VBA macro for Microsoft Excel 2010.
Some of the modules in my project would really cry out for subclasses, but I already understood that inheritance is not supported.
Knowing that, I went the hard way and implemented all the methods again in each module using an interface.
However, now I experience that a method that only occures in one of the modules (but not in the interface) throws an exception:
Method or data member not found!
I am not entirely sure but I have the feeling that this is somehow related to the interface.
Therefore I’d like to know the following:
- When implementing an interface in a module in VBA, is it still possible to write additional public subs for this module?
- If it’s not possible, what would be the correct pattern to append certain functionality to a module that implements an interface?
If you declare a variable as the interface class, you can only call methods/properties of that interface, regardless of any other methods/properties exposed by the actual object type itself.