I have several dialog classes which has a lot of common data but has differences in how each class handles the data. Now I want this common data to be defined in one parent class so each class doesn't have its own individual members but how can I do that given a dialog class is derived from CDialog in the first place? Is there any neat way other than multiple inheritance? I have never seen multiple inheritance used in any code and is discouraged by books..is that so?

My situation is very simple to below but that member variables are a lot and more complicated:

Suppose you have 4 dialogs each has its two integer member variables. The first one divides them, the 2nd on subtracts, the third multiply and 4th divides. Now I would want a base class which contain the two numbers that each class operates on but how do I define such a class so that I can derive each final dialog class from it? This will ideally sit between CDialog and CMyDialog in hierarchy but how to define it? All dialogs are direct derivatives of CDialog!