C语言/C++ 之 继承与派生、多态性与虚函数（4/5）

一、实验目的： 1.了解面向对象的程序设计的特点、思想，了解类的封装性和信息隐蔽。 2.掌握类和对象的定义和作用，熟练应用类和对象。 3.掌握类的成员函数的定义，熟练定义、应用类的成员函数。 4.掌握对象成员的引用，熟练应用对象成员的引用。 5.掌握构造函数、析构函数，要求熟练应用。

二、实验内容 编程实现：分析程序 程序代码： #include <iostream.h> class base {   int n; 扫描二维码关注公众号，回复： 15496707 查看本文章 public:     base(int a)     {   cout<<"constructing base class "<<endl;        n=a;        cout<<"n="<<n<<endl;     }     ~base(){ cout<<"destructing base blass"<<endl; } }; class subs:public base {   int m; public:     subs(int a,int b):base(a)     {   cout<<"constructing sub class "<<endl;        m=b;        cout<<"m="<<m<<endl;     }     ~subs(){ cout<<"destructing sub blass"<<endl;   } }; void main() {   subs s(1,2);　 　} 程序测试及运行结果： 编程实现： 分析程序 程序代码： #include <iostream.h> class A {   int a; public: A(int i){ a=i;   cout<<"constructing class A"<<endl;  } void print(){  cout<<a<<endl; } ~A(){ cout<<"destructing class A"<<endl; } }; class B1:public A {   int b1; public: B1(int i,int j):A(i) {       b1=j; cout<<"constructing class B1"<<endl;      } void print() {   A::print();     cout<<b1<<endl; } ~B1(){ cout<<"constructing class B1"<<endl;  } }; class B2:public A {   int b2; public: B2(int i,int j):A(i) {       b2=j; cout<<"constructing class B2"<<endl;      } void print() {   A::print();     cout<<b2<<endl; } ~B2(){ cout<<"constructing class B2"<<endl;  }}; class C:public B1,public B2 {   int c; public: C(int i,int j,int k,int l,int m):B1(i,j),B2(k,l),c(m) {   cout<<"constructing class C"<<endl; } void print() {   B1::print(); B2::print(); cout<<c<<endl;} ~C(){  cout<<"destructing class C"<<endl;}}; void main() {   C c1(1,2,3,4,5); c1.print();} 程序测试及运行结果： 编程实现：分别声明Teacher(教师)类和Cadre(干部)类， 采用多重继承方式由这两个类派生出新类Teacher_Cadre(教师兼干部)类。 程序代码： #include<iostream> #include<string> using namespace std; class Teacher {   public:        Teacher(string nam,int a,char s,string tit,string ad,string t);        void display();     protected:        string name;//姓名        int age; //年龄        char sex;// 性别        string title;//职称        string addr;//地址        string tel;//电话 }; Teacher::Teacher(string nam,int a,char s,string tit,string ad,string t):name(nam),age(a),sex(s),title(tit),addr(ad),tel(t) {} void Teacher::display() {     cout<<"name:"<<"姓名"<<endl;        cout<<"age:"<<"年龄"<<endl;     cout<<"sex:"<<"性别"<<endl;     cout<<"title:"<<"职称"<<endl;     cout<<"address:"<<"地址"<<endl;     cout<<"tel:"<<"电话"<<endl; } class Cadre {     public:        Cadre(string nam,int a,char s,string p,string ad,string t);        void display();     protected:        string name;        int age;        char sex;        string post;        string addr;        string tel; }; Cadre::Cadre(string nam,int a,char s,string p,string ad,string t):name(nam),age(a),sex(s),post(p),addr(ad),tel(t) {} void Cadre::display() {     cout<<"name:"<<name<<endl;     cout<<"age:"<<age<<endl;     cout<<"sex:"<<sex<<endl;     cout<<"post:"<<post<<endl;     cout<<"address:"<<addr<<endl;     cout<<"tel:"<<tel<<endl; } class Teacher_Cadre:virtual public Teacher,virtual public Cadre {     public:        Teacher_Cadre(string nam,int a,char s,string tit,string p,string ad,string t,float w);        void show();     private:        float wages; }; Teacher_Cadre::Teacher_Cadre(string nam,int a,char s,string tit,string p,string ad,string t,float w):Teacher(nam,a,s,tit,ad,t),Cadre(nam,a,s,p,ad,t),wages(w) //这里构造函数由于是一个人的名字，就可以用同一个nam,a,s {} void Teacher_Cadre::show() {     Teacher::display();//引用须指明作用域，否则会出现二义性     cout<<"post:"<<Cadre::post<<endl;     cout<<"wages:"<<wages<<endl; } int main() {     Teacher_Cadre teacher_cadre1("Wang-li",50,'f',"prof.","president","135 Beijing Road,Shanghai","(021)61234567",1534.5);     teacher_cadre1.show();     return 0; } 程序测试及运行结果：

未完待续。。。