C++虚函数的实现机制是通过一个vtable表，指向子类的虚函数地址。
另外，如果不是虚函数，则不能实现用父类引用调用子类方法。
#include <windows.h>
#include <iostream>
using namespace std; class CBase
{
public:
void fun()
{
cout << "CBase::fun" << endl;
} virtual void vfun1()
{
cout << "CBase::vfun1" << endl;
} virtual void vfun2()
{
cout << "CBase::vfun2" << endl;
}
}; class CDerive:public CBase
{
public:
void fun()
{
cout << "CDerive::fun" << endl;
} virtual void vfun1()
{
cout << "CDerive::vfun1" << endl;
}
}; int main(int argc, TCHAR* argv[])
{
cout << "hello world!" << endl;
CDerive derive;
CBase* pBase = (CBase*)(&derive);
pBase->fun();
pBase->vfun1();
pBase->vfun2(); cout << hex << *((int *)(*((int *)&derive))) << endl;
cout << hex << *((int *)(*((int *)&derive)) + ) << endl; cin.get();
return ;
}