简单派生类的构造函数

    1. #include<bits/stdc++.h>
    2. using namespace std;
    4. /**
    5.  * 简单派生类的构造函数
    6.  * */
    7. class Student {
    8.     public:
    9.         Student(int n, string nam) {
    10.             num = n;
    11.             name = nam;
    12.         }
    13.     protected:
    14.         int num;
    15.         string name;
    16. };
    18. class Student1: public Student {
    19.     public:
    20.         Student1(int n, string nam, int a): Student(n, nam) {
    21.             age = a;
    22.         }
    24.         void show() {
    25.             cout<<"num:"<<num<<endl;
    26.             cout<<"name:"<<name<<endl;
    27.             cout<<"age:"<<age<<endl;
    28.         }
    29.     private:
    30.         int age;
    31. };
    32. int main() {
    33.     Student1 stud1(10010, "zhangsan", 19);
    34.     stud1.show();
    36.     return 0;
    37. }

    包含子对象派生类的构造函数

    1. #include<bits/stdc++.h>
    2. using namespace std;
    4. /**
    5.  * 包含子对象派生类的构造函数
    6.  * */
    7. class Student {
    8.     public:
    9.         Student(int n, string nam) {
    10.             num = n;
    11.             name = nam;
    12.             cout<<"construct: Student "<<"名字为："<<name<<endl;
    13.         }
    14.         void display() {
    15.             cout<<"num:"<<num<<endl;
    16.             cout<<"name:"<<name<<endl;
    17.         }
    18.     protected:
    19.         int num;
    20.         string name;
    21. };
    23. class Student1: public Student {
    24.     public:
    25.         Student1(int n, string nam, int a, string ma, int n1,string nam1): Student(n, nam), monitor(n1, nam1) {
    26.             age = a;
    27.             major = ma;
    28.             cout<<"construct: Student1"<<endl;
    29.         }
    31.         void show() {
    32.             cout<<"the student is :"<<endl;
    33.             display();
    34.             cout<<"age:"<<age<<endl;
    35.             cout<<"major:"<<major<<endl;
    36.         }
    37.         void show_monitor() {
    38.             cout<<"monitor is:"<<endl;
    39.             monitor.display();
    40.         }
    41.     private:
    42.         int age;
    43.         string major;
    44.         Student monitor;
    45. };
    46. int main() {
    47.     Student1 stud1(10010, "zhangsan", 19, "math", 10001, "monitor");
    48.     stud1.show();
    49.     stud1.show_monitor();
    51.     return 0;
    52. }

    析构函数

    1. #include<bits/stdc++.h>
    2. using namespace std;
    4. /**
    5.  * 析构函数
    6.  * */
    7. class A {
    8.     public:
    9.         A() {
    10.             cout<<"constrcu A" <<endl;
    11.         }
    12.         ~A() {
    13.             cout<<"destruct A"<<endl;
    14.         }
    15. };
    16. class B: public A {
    17.     public:     
    18.         B() {
    19.             cout<<"construct B"<<endl;
    20.         }
    21.         ~B() {
    22.             cout<<"destruct B"<<endl;
    23.         }
    24. };
    25. int main() {
    26.     B b;
    27.     return 0;
    28. }

    输出

    1. constrcu A
    2. construct B
    3. destruct B
    4. destruct A