c语言实现面向对象编程

1.通用校验器接口(validator.h)

#ifndef VALIDATOR_H_INCLUDED
#define VALIDATOR_H_INCLUDED

#include<stdbool.h>

typedef struct _Validator{
    bool (*const validate)(struct _Validator *pThis, int value);
}Validator;

typedef struct{
    Validator isa;    //结构体成员
    const int min;
    const int max;
} RangeValidator;

 typedef struct{
    Validator isa;    //结构体成员
    bool isEven;
 } OddEvenValidator;

bool validateRange(Validator *pThis, int value); // 范围校验器函数
bool validateOddEven(Validator *pThis, int value); // 奇偶校验器函数
#define newRangeValidator(min, max) {{validateRange}, (min), (max)} // 初始化RangeValidator
#define newOddEvenValidator(isEven) {{validateOddEven}, (isEven)} //  初始化OddEvenValidator

#endif // VALIDATOR_H_INCLUDED

2.通用校验器接口实现(validator.c)

#include "validator.h"

bool validateRange(Validator *pThis, int value)
{
    RangeValidator *pRangeValidator = (RangeValidator *)pThis;
    return pRangeValidator -> min <= value && value <= pRangeValidator -> max;
}

bool validateOddEven(Validator *pThis, int value)
{
    OddEvenValidator *pOddEvenValidator = (OddEvenValidator *)pThis;
    return (!pOddEvenValidator -> isEven && (value % 2)) || (pOddEvenValidator -> isEven && !(value % 2));
}

3.通用校验器使用范例程序

#include <stdio.h>
#include "validator.h"

int main()
{
   int  num;
   RangeValidator rangeValidator = newRangeValidator(1, 10);// 初始化RangeValidator
   Validator *pValidator = &rangeValidator.isa;
   printf("Pease input an integer: ");
   scanf("%d",&num);
   printf("
");

   if(pValidator->validate(pValidator,num) == true)
   {
        printf("The %d in range of 1 to 10
",num);
   }
   else
   {
        printf("The %d not in range of 1 to 10
",num);
   }
    printf("
");

   OddEvenValidator oddEvenValidator = newOddEvenValidator(true);// 初始化OddEvenValidator
   pValidator = &oddEvenValidator.isa;

    printf("Pease input an integer: ");
   scanf("%d",&num);
   printf("
");

   if(pValidator->validate(pValidator,num) == true)
   {
        printf("The %d is an even.
",num);
   }
   else
   {
        printf("The %d is an odd.
",num);
   }
    return 0;
}