diffrence between void and virtual void

Hello everybody,

can somebody say me when i have to use virtual void?And the difference between virtual void and void?


thx

The virtual keyword defines that a class function may be overridden in a derived class.
So the derived class may have an implementation of a function with same name and argument list but with different/extended functionality.

Edit: http://www.cppreference.com/keywords/virtual.html

virtual keyword has nothing to do with return type of a method. It only tells that the following method is virtual (you can skip virtual in subclasses).

Try this:

Code:

---

#include <iostream>
 
class A
{
   public:
      A() {}
      void nonVirt() { std::cerr << "A::nonVirt()" << std::endl; }
      virtual void virt() { std::cerr << "A::virt()" << std::endl; }
      virtual ~A() {}
};
 
class B : public A
{  
   public:
      void nonVirt() { std::cerr << "B::nonVirt()" << std::endl; }
      void virt() { std::cerr << "B::virt()" << std::endl; }
};
 
int main()
{
   A a;
   B b;
   A *ptr = &b;
 
   a.nonVirt();
   a.virt();
   b.nonVirt();
   b.virt();
   ptr->nonVirt();
   ptr->virt();
 
   return 0;
}

---