Re: dynamic cast and typeid

Alf P. Steinbach ha scritto:


ok, I try to be as concise as I can.

//this one is linked in a.so file:

//file objects.h

#include <string>

class A {
public:
virtual std::string getClassName() const;
}

virtual ~A();

};

class B : public A {};

//file objects.cpp

std::string A::getClassName() const{
   return typeid(*this).name();
}

A::~A() {}

//this one is linked in b.so file

//file container.h

#include <iostream>
#include "objects.h"

class Container {
public:
   Container();

   void setObject(A* o);

   template<typename T>
   T *getObjectAs() {
     T* t = dynamic_cast<T*>(var);

     if(t == NULL)
       std::cout << "Object is of type " << var->getClassName() <<
       " but you required " << typeid(T).name() << std::endl;

    return t;
   }

private:
A* var;

};

//container.cpp

void Container::setObject(A* o) {
var = o;
}

//now main.c

#include "container.h"
#include "objects.h"

int main() {

B* b = new B();
Container cont;

cont.setObject(b);
B* b1 = cont.getObjectAs<B>();

return 0;
}

Well, The correponding method in my real application prints out:
Object is of type B but you required B

hope this helps in understanding what the code I have does.

ty again.