使用reinterpret_cast的危险

关键字： c++ cast

 

// Cast.cpp : Defines the entry point for the console application.
//

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

using namespace std;

class Base
{
public:

    virtual void func1() = 0;
    virtual void func2() = 0;
};

class A
{
    virtual void func3();
};

void A::func3()
{
    cout<<"func3"<<endl;
}

class B : public A, public Base
{
public:
    virtual void func1();
    virtual void func2();
};

void B::func1()
{
    cout<<"func1"<<endl;
}

void B::func2()
{
    cout<<"func2"<<endl;
}


void DynamicCast()
{
    A* pA = new B();
    Base* pBase = dynamic_cast<Base*>(pA);//Work fine
    pBase->func1();
    pBase->func2();
}

void StaticCast()
{
    A* pA = new B();
    //Base* pBase = static_cast<Base*>(pA);//Compiler error
    //pBase->func1();
    //pBase->func2();
}

void ReinterpretCast()
{
    A* pA = new B();
    Base* pBase = reinterpret_cast<Base*>(pA);
    pBase->func1();
    pBase->func2();//run-time error: Access violation
}

int _tmain(int argc, _TCHAR* argv[])
{
    DynamicCast();
    ReinterpretCast();

    return 0;
}