C实例---写入文件

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

struct student_score
{
char name[10];
int num;
int Chinese;
int Math;
int English;
} score[100];

void Save(char *name, int n)
{
FILE *fp;
int i;
/* FILE * fopen(const char *restrict filename, const char *restrict mode); */
if ( (fp = fopen(name, "wb")) == NULL )
{
printf("Line %d : Can not open file!\n", __LINE__);
exit(1);
}
for (i = 0; i < n; i ++)
{
/* size_t fwrite(const void *restrict ptr, size_t size, size_t nitems,
FILE *restrict stream); */
if (fwrite(&score[i], sizeof(struct student_score), 1, fp) != 1)
{
printf("Line %d : file write error!\n", __LINE__);
}
}
/* int fclose(FILE *stream); */
fclose(fp);
}

void Show(char *name, int n)
{
int i;
FILE *fp;
if ( (fp = fopen(name, "rb")) == NULL )
{
printf("Line %d : Can not open file!\n", __LINE__);
}
for (i = 0; i < n; i ++)
{
/* size_t read(void *restrict ptr, size_t size, size_t nitems,
FILE *restrict stream); */
fread(&score[i], sizeof(struct student_score), 1, fp);
printf("%-10s%4d%4d%4d%4d\n", score[i].name, score[i].num, score[i].Chinese,
score[i].Math, score[i].English);
}
fclose(fp);
}

int main ()
{
int i,n;
char filename[50];
printf("How many students in your class?\n");
scanf("%d", &n);
printf("Please input filename:\n");
scanf("%s",filename);
printf("Please input name, number, Chinese, Math and English: \n");
for (i = 0; i < n; i ++)
{
printf("No.%d\n", i+1);
scanf("%s%d%d%d%d",score[i].name, &score[i].num, &score[i].Chinese,
&score[i].Math, &score[i].English);
Save(filename, n);
}
Show(filename, n);
return 0;
}