C语言实现面向对象

person为父类，child为子类

代码实现如下

person.h

typedef struct Person {
// 模拟类的成员属性
char *name;
int age;
// 模拟类的方法
void (*showInfo)(Person_T);
int (*compare)(void *,void *,int (*compare)(void *,void *));
}*Person_T;

// 模拟对象的创建
Person_T Person_new(char *name,int age);
void Person_free(Person_T person);

person.c

#include"person.h"
#include<stdio.h>
#include<stdlib.h>

// 打印属性信息
void Person_info(Person_T person){
printf("name:%s age:%d\n",person->name,person->age);
}

// 信息比较函数
int Person_compare(void *a,void *b,int (*compare)(void *,void *)){
return (*compare)(a,b);
}

// 创建对象并初始化
Person_T Person_new(char *name,int age){
Person_T person = malloc(sizeof(struct Person));
// 初始化成员属性
person->name = name;
person->age = age;
// 初始化方法
person->showInfo = Person_info;
person->compare = Person_compare;
return person;
}

// 释放指针对内存的引用
void Person_free(Person_T person){
free(person);
}

child.h

#include"person.h"

typedef struct Child {
// 模拟类的成员属性
Person_T person;
float hight;
}*Child_T;

// 模拟对象的创建
Child_T Child_new(char *name,int age,float hight);
void Child_free(Child_T child);

child.c

#include"child.h"
#include<stdio.h>
#include<stdlib.h>

// 打印属性信息
void Child_info(Child_T child){
printf("name:%s age:%d height:%.2f\n",child->person->name,child->person->age,child->hight);
}

// 创建对象并初始化
Child_T Child_new(char *name,int age,float hight){
Child_T child = malloc(sizeof(struct Child));
// 初始化成员属性
child->person = Person_new(name,age);
child->hight = hight;
// 重写继承父类的showInfo方法
child->person->showInfo = Child_info;
return child;
}

// 释放指针对内存的引用
void Child_free(Child_T child){
Person_free(child->person);
free(child);
}

test.c

#include<stdio.h>
#include<string.h>
#include"child.h"

// 整型数字的比较函数
int compareInts(void *a,void *b){
int *ta = (int *)a;
int *tb = (int *)b;
return (*ta - *tb);
}

int main(){

// 创建对象
Person_T person = Person_new("mark",20);
Child_T child = Child_new("jack",21,178.0f);

// 通过对象名调用打印属性信息方法
person->showInfo(person);
child->person->showInfo(child);

// 通过对象名调用信息比较方法
person->compare(person->name,child->person->name,strcmp);
child->person->compare(&(person->age),&(child->person->age),compareInts);

// 打印比较结果
 printf("%d\n",person->compare(person->name,child->person->name,strcmp));
 printf("%d\n",child->person->compare(&(person->age),&(child->person->age),compareInts));

// 释放指针对内存的引用
 Person_free(person);
 Child_free(child);

return 0;
}