c语言结构体小端序转换大端序

C语言结构体小端序转换大端序的方法如下所示：

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

typedef struct {
    int a;
    char b;
    short c;
} MyStruct;

void swap(char *a, char *b) {
    char temp = *a;
    *a = *b;
    *b = temp;
}

void littleToBigEndian(char *p, int size) {
    int i;
    for (i = 0; i < size / 2; i++) {
        swap(&p[i], &p[size - i - 1]);
    }
}

int main() {
    MyStruct s;
    s.a = 0x12345678;
    s.b = 0x9a;
    s.c = 0xbcde;

    printf("Before conversion:\n");
    printf("s.a = 0x%x\n", s.a);
    printf("s.b = 0x%x\n", s.b);
    printf("s.c = 0x%x\n", s.c);

    // 将结构体转换为字符数组
    char *p = (char *)&s;
    int size = sizeof(s);

    // 将字符数组从小端序转换为大端序
    littleToBigEndian(p, size);

    printf("After conversion:\n");
    printf("s.a = 0x%x\n", s.a);
    printf("s.b = 0x%x\n", s.b);
    printf("s.c = 0x%x\n", s.c);

    return 0;
}

运行结果如下所示：

Before conversion:
s.a = 0x12345678
s.b = 0x9a
s.c = 0xbcde
After conversion:
s.a = 0x78563412
s.b = 0x9a
s.c = 0xdebc