类的引用和复制

#include<iostream>

using namespace std;

class base{

public:

base(){}

virtual void func(int i = 12)

{

cout<<"base "<<i<<endl;

}

};

class Derived:public base{

public:

Derived(){}

virtual void func(int i = 22)

{

cout<<"Derived "<<i<<endl;

}

};

int main()

{

Derived d;

base& b1 = d;

base b2 = d;

b1.func();

b2.func();

d.func();

return 0;

}

输出： Derived 12

base 12

Derived 22

1.默认参数静态绑定。

2.c++通过基类的引用或指针调用虚函数时，才发生动态绑定。

3.base& b1 = d; 把d地址赋给b1； base b2 = d;把d中base内容赋给b2；