使用c語言實現面向對象之NEW的實現

//類型需要和平臺相關這裏使用的是32位平臺
typedef unsigned int  u32;
typedef unsigned short u16;
typedef unsigned char  u8;

#include "string.h"
#include "stdio.h"
#include "stdlib.h"

//第一步將所有的功能函數抽象出來
typedef struct
{
    void(*addSet)(void* instance,int a,int b);
    int(*addGet)(void* instance);
    void* instance;
}ModeNameAbstractFunc_t;
//私有變量
typedef struct{
    int sum;
    char* b;//亂定義的
    u8 c[20];//亂定義的
    void (*d)(void);//亂定義的
}PrivateVariable_t;
static void ModeNameAddSet(void* instance,int a,int b)
{
    PrivateVariable_t *p = (PrivateVariable_t*)instance;
    p->sum = (a+b);
}
static int ModeNameAddGet(void* instance)
{
    PrivateVariable_t *p = (PrivateVariable_t*)instance;
    return p->sum;
}
ModeNameAbstractFunc_t *ModeNameNew(void)
{
    ModeNameAbstractFunc_t *p = (ModeNameAbstractFunc_t*)malloc(sizeof(ModeNameAbstractFunc_t));
    p->addSet  = ModeNameAddSet;
    p->addGet  = ModeNameAddGet;
    //每次new 分配內存
    p->instance = (PrivateVariable_t*)malloc(sizeof(PrivateVariable_t)) ;
    return p;
}
//使用
int main()
{
    int A =0;
    ModeNameAbstractFunc_t *p1 = ModeNameNew();
    ModeNameAbstractFunc_t *p2 = ModeNameNew();
    p1->addSet(p1->instance,1,2);
    A = p1->addGet(p1->instance);
    printf("first this result is %d\n",A);
    p2->addSet(p2->instance,3,4);
    A = p1->addGet(p1->instance);
    printf("then this result is %d\n",A);//調用了同樣的方法原來的值沒有變還是3
}

//C語言在線測試網站
//http://www.dooccn.com/c/