Re: Forward declaration of managed class: howto?

From:

David Wilkinson <no-reply@effisols.com>

Newsgroups:

microsoft.public.vc.language

Date:

Wed, 24 Sep 2008 11:09:51 -0400

Message-ID:

<OoiFYelHJHA.2580@TK2MSFTNGP05.phx.gbl>

Armin Zingler wrote:

Thanks for clarification! Now it's clear. Though, what I don't like is
splitting one class into two or three parts. Everytime I change anything, I
have to change it twice. In addition, the class' member function
definitions
seem to stand "nowhere", i.e. not encapsulated by anything like "class C
{...}". And, the private members (fields) are not where I expect them.
I want to declare them at the same location where I implement (=define) the
member functions. What if "int member" is private? Then I don't need it in
the header file because another class can not acces it anyway. Well, I'll
have to live with it.

Maybe adding an interface will make things simpler. Will have to try...

Armin:

The method (member function) definitions may appear to be "nowhere", but they
are scoped with the class name (and namespace name if any).

As I explained in my other answer, the private members must be in the class
definition so that the compiler knows how big the object is.

There are two way to hide this information from clients of the class:

1. Abstract Base Class (interface)

2. Pointer to Implementation (PIMPL).

--
David Wilkinson
Visual C++ MVP