C++学习记录（四）分文件编程，拷贝构造函数

程序虽然能跑通，但是有提示内存泄漏。

 1 #ifndef STUDENT_H
 2 #define STUDENT_H
 3 #include <iostream>
 4 
 5 using namespace std;
 6 
 7 class Student
 8 {
 9     string name;
10     int age;
11     static int score;
12     int *p;
13 
14 public:
15     Student() = default;
16     Student(string name, int age);
17     Student(Student& Student); // 拷贝构造函数
18 
19     ~Student() ;
20 
21     void showInfo();
22     int getScore();
23 
24     int getAge();
25     string getName();
26 };
27 
28 #endif // STUDENT_H
 1 #include "student.h"
 2 
 3 Student::Student(string name, int age)
 4 {
 5     this->name = name;
 6     this->age = age;
 7     p = new int[10];
 8     cout << "This is the Student class construction !" << endl;
 9 }
10 
11 // 浅拷贝(类中有指针时，新拷贝对象和拷贝对象指向内存中的同一地址，故不能多次释放)
12 Student::Student(Student &student)
13 {
14     this->name = student.name;
15     this->age = student.age;
16     cout << "This is the Student class copy construction !" << endl;
17 
18     // 深拷贝(类中有指针)
19     this->p = new int[10];
20     memcpy(this->p, student.p, sizeof(int[10])); // 内存拷贝
21 }
22 
23 Student::~Student()
24 {
25     delete []p;
26 }
27 
28 void Student::showInfo()
29 {
30     cout << "name is: " << name << ", age: " << age << ", score: " << getScore() << endl;
31 }
32 
33 int Student::getScore()
34 {
35     return score;
36 }
37 
38 int Student::getAge()
39 {
40     return age;
41 }
42 
43 string Student::getName()
44 {
45     return name;
46 }
47 
48 int Student::score = 100;
 1 #include <iostream>
 2 
 3 using namespace std;
 4 
 5 #include "student.h"
 6 
 7 /*
 8 Student compair(Student stu1, Student stu2)
 9 {
10     return stu1.getAge() > stu2.getAge() ? stu1: stu2;
11 }
12 */
13 Student& compair(Student& stu1, Student& stu2)
14 {
15     return stu1.getAge() > stu2.getAge() ? stu1: stu2;
16 }
17 
18 int main()
19 {
20     Student stu1;
21     Student stu2("zhangsan", 18);
22 
23     stu1.showInfo();
24     cout << "-------1------" << endl;
25     stu2.showInfo();
26 
27     Student stu3 = stu2;                // 拷贝构造函数的两种格式
28     Student stu4(stu2);
29     cout << "-------2------" << endl;
30     stu3.showInfo();
31 
32     // 拷贝构造函数
33     // 当定义对象需要另一个对象初始化时，就会调用拷贝构造函数.
34     // 采用引用的方式，指向同一个内存空间，就不会调用拷贝构造函数，节省空间
35     cout << "------3-------" << endl;
36     Student stu5("Lisi", 20);
37 
38     // 当函数传参，函数返回时，会调用拷贝构造函数
39     cout << "The older student is: " << compair(stu2, stu5).getName() << endl;
40 
41     cout << "Hello World!" << endl;
42     return 0;
43 }

 

posted @ 2022-05-07 22:20  Z_He  阅读(34)  评论(0)  编辑  收藏  举报