深拷贝和浅拷贝

来源：互联网发布：java8 javascript 编辑：程序博客网时间：2024/05/20 21:43

1.编译器默认浅拷贝

2.深拷贝需要再次分配内存

#define  _CRT_SECURE_NO_WARNINGS #include <stdlib.h>#include <string.h>#include <stdio.h>typedef struct Teacher{char name[64];int age ;char *pname2;}Teacher;//编译器的=号操作,只会把指针变量的值,从from  copy 到 to,但 //不会 把指针变量 所指 的 内存空间 给copy过去..//浅copy//结构体中套一个 1级指针 或 二级指针 //如果 想执行深copy,再显示的分配内存void copyTeacher(Teacher *to, Teacher *from){*to = *from;to->pname2 = (char *)malloc(100);strcpy(to->pname2, from->pname2);//memcpy(to, from , sizeof(Teacher));}void main51(){Teacher t1;Teacher t2;strcpy(t1.name, "name1");t1.pname2 = (char *)malloc(100);strcpy(t1.pname2, "ssss");//t1 copy t2copyTeacher(&t2, &t1);if (t1.pname2 != NULL){free(t1.pname2);t1.pname2 = NULL;}if (t2.pname2 != NULL){free(t2.pname2);t2.pname2 = NULL;}printf("hello...\n");system("pause");return ;}

3.内存模型

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