C++ 编译多态 运行多态

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多态是什么？简单来说，就是某段程序调用了一个API接口，但是这个API有许多种实现，根据上下文的不同，调用这段API的程序，会调用该API的不同实现。今天我们只关注继承关系下的多态。<br><br>#include <iostream> #include <stdio.h>   using namespace std;   class Father { public:     int m_fid;     Father()     {         m_fid = 1;     }     virtual void v_print()     {         printf("Father v_print() %d\n", m_fid);     }       void print()     {         printf("Father print() %d\n", m_fid);     } };   class Child : public Father { public:     int m_cid;     Child()     {         m_cid = 2;     }     void v_print()     {         printf("Child v_print() %d:%d\n", m_fid, m_cid);     }       void print()     {         printf("Child print() %d:%d\n", m_fid, m_cid);     } };   int main(void) {     Father *f = new Father();     Father *fc = new Child();     Child *c = new Child();     Child *cf = (Child*)new Father();         f->print();     f->v_print();       fc->print();//静态     fc->v_print();//动态       c->print();     c->v_print();           cf->print();//静态     cf->v_print();//动态           return 0; }

 运行结果为：

Father print() 1
Father v_print() 1
Father print() 1
Child v_print() 1:2
Child print() 1:2
Child v_print() 1:2
Child print() 1:0
Father v_print() 1