Hi,
In the following program, eventhogh two member function declared under
private section of the derived class are accessable by derived class
pointer.
Please clarify me how can derived class pointer acess private member
functions.
private member functions
#include <stdio.h>
#include <iostream>
using namespace std;
class Base
{
public :
virtual void virFun1 (int i);
virtual void virFun2 (double d);
};
void Base :: virFun1(int i)
{
cout <<" Base :: virFun1 ::
"<<i<<endl;
}
void Base :: virFun2(double d)
{
cout <<" Base :: virFun2 ::
"<<d<<endl;
}
class Derived : public Base
{
private : // PRIVATE ????????????
virtual void virFun1 (int i);
virtual void virFun2 (double d);
};
void Derived :: virFun1(int i)
{
cout <<" Derived :: virFun1 ::
"<<i<<endl;
}
void Derived :: virFun2(double d)
{
cout <<" Derived :: virFun2 ::
"<<d<<endl;
}
int main ()
{
Base *d = new Derived;
d -> virFun1 (10);
d -> virFun2 (10.10);
}
Thanks in advance
Bangalore 3 2688
Bangalore wrote: Hi,
In the following program, eventhogh two member function declared under private section of the derived class are accessable by derived class pointer. Please clarify me how can derived class pointer acess private member functions.
private member functions #include <stdio.h> #include <iostream> using namespace std;
class Base {
public :
virtual void virFun1 (int i); virtual void virFun2 (double d); };
void Base :: virFun1(int i) { cout <<" Base :: virFun1 :: "<<i<<endl;
}
void Base :: virFun2(double d) { cout <<" Base :: virFun2 :: "<<d<<endl; }
class Derived : public Base { private : // PRIVATE ????????????
virtual void virFun1 (int i); virtual void virFun2 (double d); };
void Derived :: virFun1(int i) { cout <<" Derived :: virFun1 :: "<<i<<endl;
}
void Derived :: virFun2(double d) { cout <<" Derived :: virFun2 :: "<<d<<endl; }
int main () { Base *d = new Derived; d -> virFun1 (10); d -> virFun2 (10.10); }
Thanks in advance Bangalore
See this FAQ: http://www.parashift.com/c++-faq-lit....html#faq-21.1
Cheers! --M
Bangalore wrote: Hi,
In the following program, eventhogh two member function declared under private section of the derived class are accessable by derived class pointer. Please clarify me how can derived class pointer acess private member functions.
private member functions #include <stdio.h> #include <iostream> using namespace std;
class Base {
public :
virtual void virFun1 (int i); virtual void virFun2 (double d); };
void Base :: virFun1(int i) { cout <<" Base :: virFun1 :: "<<i<<endl;
}
void Base :: virFun2(double d) { cout <<" Base :: virFun2 :: "<<d<<endl; }
class Derived : public Base { private : // PRIVATE ????????????
virtual void virFun1 (int i); virtual void virFun2 (double d); };
void Derived :: virFun1(int i) { cout <<" Derived :: virFun1 :: "<<i<<endl;
}
void Derived :: virFun2(double d) { cout <<" Derived :: virFun2 :: "<<d<<endl; }
int main () { Base *d = new Derived; d -> virFun1 (10); d -> virFun2 (10.10); }
Thanks in advance Bangalore
Hello,
In your example, Base class has virtual functions . At run time "d"
points to derived class. So it has all rights to access its
members.....
-Sabi-
Bangalore wrote: Hi,
In the following program, eventhogh two member function declared under private section of the derived class are accessable by derived class pointer.
They are accessed via the base-class pointer. They are public in the
base class, therefore when using the base as interface (or accessing
them via base pointer), they should be public. Accessing them through
the derived pointer, this would not work.
class Base
{
public:
virtual void v1() = 0;
};
class Derived
{
public:
// ...constructor etc.
private:
//Note: v1 not private when accessed through baseclass reference
or pointer!
virtual void v1()
{
//...some code
};
}
Base* bp( new Derived() );
Derived* dp( new Derived() );
bp->v1(); //Ok, as public when accessed through base ptr
dp->v1(); //Error - private!
Please clarify me how can derived class pointer acess private member functions.
You weren't using the derived pointer in your example, you were using
the base private member functions #include <stdio.h>
Use #include <cstdio> over here...
Kind regards,
Werner This thread has been closed and replies have been disabled. Please start a new discussion. Similar topics |
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