is it correct behavior of Virtual function ?

[Pallav singh]

Hi All ,

in the below code i have created derived class object and in base
class we have virtual function.
i am using object slicing to copy only base part of it........ why is
not VTable getting updated Properly

Since in derived object's base part have address of derived class
virtual function address
Why its Not getting copied to base part with object slicing

is is behaving properly ?

#include <iostream>
using namespace std;

class Base
{
public :
virtual void func()
{ cout<<" I am inside Base "<<endl; }
};

class derived : public Base
{
public :
void func()
{ cout<<" I am inside Derived "<<endl; }
};

int main()
{
derived obj;
Base b = obj;
b.func();
return 0;
}
I am inside Base


Thanks
Pallav Singh

 

[Juha Nieminen]

derived obj;
Base b = obj;
b.func();

'b' is an object of type Base, and naturally Base::func() will be
called. It doesn't matter how 'b' has been initialized. Initialization
doesn't change its type.

There's a difference between an *object* of type Base and a *pointer*
to Base. A pointer doesn't fix the object's type.