Cpp > Programs

Cpp - Dynamic Casting

#include <iostream>
#include <exception>
using namespace std;

class Base
{
virtual void dummy() {}
};
class Derived: public Base
{
int a;
};

int main ()
{
  try
  {
    Base * bptrD = new Derived;
    Base * bptrB = new Base;
    Derived * dptr;

    dptr = dynamic_cast<Derived*>(bptrD);
    if (dptr==0) cout << "Null pointer on first type-cast" << endl;

    dptr = dynamic_cast<Derived*>(bptrB);
    if (dptr==0) cout << "Null pointer on second type-cast" << endl;
  }
catch (exception& e)
{
  cout << "Exception: " << e.what();
}
  return 0;
}