C++ 類的多態(方法的重載與繼承)

直接上例子:

 

#include "stdafx.h"
#include

using namespace std;

 

class Base
{
public:
 void f(int x){cout << "Base::f(int)" <<endl;}
 void f(float x){cout << "Base::f(float)" <<endl;}
 virtual void g(void){cout << "Base::g(void)" << endl;}
};

 

class Derived : public Base
{
public:
 virtual void g(void){cout << "Derived::g(void)" << endl;}
};

 

int _tmain(int argc, _TCHAR* argv[])
{
 Derived d;
 Base *pb = &d;
 Base b;
 pb->f(42);
 pb->f((float)4.2);
 pb->g();
 cout<<endl;

 d.f(42);
 d.f((float)4.2);
 d.g();
 cout<<endl;

 b.g();
 cout<<endl;

 int n;
 cin >> n;
 return 0;
}

 

執行結果:

 

結論:

      方法被重載後會根據參數的類型自動調用相應的方法

      子類重寫了父類的抽象方法後,除非直接實例化父類,要不然後子類的方法會覆蓋父類的方法