class Base
{
  public:
    virtual void foo()
    {}
};

class Derived: public Base
{
  public:
    virtual void foo()
    {}
};

int main()
{
    Base *pBase = NULL;
    Base objBase;
    Derived objDerived;

    pBase = &objDerived;
    pBase->foo();

    /*Here Derived class foo will be called, but i want this to call 
    a base class foo. Is there any way for this to happen? i.e. through 
    casting or something? */
}