C++中浅拷贝与深拷贝的详解及其作用介绍

目录

• 概述
• 对象的赋值
• 对象的复制
• 对象复制的用途

• 建立一个新对象
• 函数的参数为类对象
• 函数的返回值为类对象

对象名1 = 对象名2;

int main() {
    Time t1(6,6,6);
    Time t2 = t1; // 对象赋值
    return 0;
}

类名 对象2(对象1);

int main() {
    Time t1(8, 8, 8);
    Time t2(t1);  // 对象的复制
    return 0;
}

int main() {
    Time t1(8, 8, 8);
    Time t2 = t1;  // 对象的复制
    return 0;
}

Time::Time(const Time& t){
    hour = t.hour;
    minute = t.minute;
    second = t.second;
}

Time t2(t1);

void fun(Time time);
using namespace std;
int main() {
    Time t1(8, 8, 8);
    fun(t1);
    return 0;
}
void fun(Time time) {
    cout << "function" << endl;
}

Time fun();
using namespace std;
int main() {
    Time t2;
    t2 = fun();
    return 0;
}
Time fun() {
    Time t1(8, 8,8);
    return t1;
}

#ifndef PROJECT2_TEST_H
#define PROJECT2_TEST_H
class Test {
public:
    int x;
    Test(int n);
    void show();
};
#endif //PROJECT2_TEST_H

#include <iostream>
#include "Test.h"
using namespace std;
Test::Test(int n) : x(n){}
void Test::show() {
    cout << x << endl;
}

#include "Test.h"
#include <iostream>
using namespace std;
int main() {
    Test *pt1 = new Test(100);
    Test *pt2 = pt1;
    pt1 -> x = 5;
    pt1 -> show();
    pt2 -> show();
	delete pt1;
	delete pt2;
    return 0;
}

#include "Test.h"
#include <iostream>
using namespace std;
int main() {
    Test a(100);
    Test b = a;
    a.x = 5;
    a.show();
    b.show();
    return 0;
}