Re: [Dev-C++] accessing derived class methods

[Per W. <pw...@ia...>]

There are solutions to everything. The problem is just to know when the
solution should be used, and when a program should be written in a
different way.

using dynamic_cast<type>(object) you can type-safely convert from a base
class pointer to a pointer for a derived object. If the object isn't a
derived class, then you will get a NULL pointer instead.

/Per W

On Mon, 19 Sep 2005, Dane Ensign wrote:

> Neeraj,
>
> Thanks for the input. I was afraid of that. I suppose this holds true
> always. I was hoping that a nested class with some friend
> declarations might provide a solution but
> I accept defeat.
>
> Thanks for clearing things up.
>
> Dane
>
> Begin forwarded message:
>
> > Dane,
> >
> >    Ideally what you are doing should work the only care which must be
> > taken is that the base class pointers must point to correct derived
> > class objects and second is that you can't access any function in
> > derived class which is not defined as virtual in base class.
> > I mean if getSpecificData() is not defined as virtual in base you can
> > not a derived version of call it using base class pointer.
> >
> > Regards
> > Neeraj
> >
> > -----Original Message-----
> > From: dev...@li...
> > [mailto:dev...@li...] On Behalf Of Dane
> > Ensign
> > Sent: Tuesday, September 20, 2005 8:09 AM
> > To: dev...@li...
> > Subject: [Dev-C++] accessing derived class methods
> >
> > Hi all,
> >
> > I have a simple base class and a few derived classes from it. My goal
> > is to build an array of pointers where I can assign derived class
> > objects into, then access the different derived class attributes
> > as needed.
> >
> > So I have an employee class. I derive a laborer, scientist, and
> > manager class from it. I build some basic virtual functions in the
> > employee class, and each derived class
> > has a couple of specific attributes that I want to call, like
> > getSpecificData().
> >
> > I made an array of base class pointers then tried accessing the
> > derived class methods, but it doesnt work. I made an array of void*
> > pointers and tried to access derived class methods and that doesnt
> > work.
> >
> > I realize that I could build a pure virtual function in the base
> > class that would only be used to access derived class atrributes, but
> > that is silly. Please can someone point* me in the right direction?
> >
> > Thanks for any help you can offer.
> >
> > Best regards,
> >
> > Dane
> > da...@de...
> >
> >
> >
> >
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>
> Dane
> da...@de...
>
>
>
>
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