奇怪的多态问题?
#include "stdafx.h"
class A
{
public:
A(){doSth();}
virtual void doSth(){printf("I am A");}
};
class B:public A
{
public:
virtual void doSth(){printf("I am B");}
};
int _tmain(int argc, _TCHAR* argv[])
{
B b;
return 0;
}
这一个为何输出"I am A"。多态跑哪去了??