对象内存布局 (1)

#include <iostream>
using namespace std;

class Base
{

public:
    int m_base;
    inline virtual void vfBase_1()
    {
        cout << "This is in Base::vfBase_1()" << endl;
    }

    inline virtual void vfBase_2()
    {
        cout << "This is in Base::vfBase_2()" << endl;
    }
};

class Derived : public Base
{
public:
    int m_derived;
};

typedef void (*VFun)(void);

// 改为template形式，因为不能确定传进来的参数是Base类型的指针还是Derived类型的指针

template<typename T>
VFun virtualFunctionPointer(T* b, int i)
{
    return (VFun)(*((int*)(*(int*)b) + i));
}

int main(void)
{
    Derived d;
    cout << "The size of Base object = \t" << sizeof(Derived) << endl;
    cout << endl;
    int i = 0;
    while(virtualFunctionPointer(&d, i))
    {
        VFun pVF = virtualFunctionPointer(&d, i++);
        pVF();
    }
    return 0;
}