Re: inheritance / overriding question

From:
"roy axenov" <r_axenov@mail.ru>
Newsgroups:
comp.lang.c++
Date:
3 Mar 2007 01:56:06 -0800
Message-ID:
<1172915766.635122.272250@p10g2000cwp.googlegroups.com>
On Mar 3, 11:42 am, "Michael" <michael5...@yahoo.com>
wrote:

#include <iostream>

class BaseClass {
    protected:
        int var;
    public:
        void setVar(int var){
            this->var = var;
            std::cout << "using BaseClass\n";
        }
        virtual void showVar() = 0;
};

class ClassA : public BaseClass {
    public:
        void setVar(int var){
            this->var = var;
            std::cout << "using ClassA\n";
        }
        void showVar(){
            std::cout << "using ClassA var is " << var;
        }
};

int main(){
    BaseClass* base;

    base = new ClassA;

    base->setVar(12);
    base->showVar();
}

why does base->setVar() call the function in the
BaseClass, not the one in ClassA?


It's what you asked for. base is a pointer to a BaseClass
object, and setVar is not a virtual function.

Shouldn't ClassA override the BaseClass function?


Nope, because you didn't ask for it.

http://www.parashift.com/c++-faq-lite/virtual-functions.html

--
roy axenov

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