使用fwrite()函数和fprintf()函数输出数据到文件时的区别

 1 #include<stdio.h>
#include<stdlib.h>
#define FWRITE

int main(){
setbuf(stdout,NULL);
struct student
{
int NUM;
char name[20];
int scores[3];
float aver;
};
FILE *fp;
struct student stus[5],test[5];
int i,j;
int num;

printf("Input the data of students:\n");
for(i=0;i<5;i++)
scanf("%d%s%d%d%d",&stus[i].NUM,stus[i].name,
&stus[i].scores[0],&stus[i].scores[1],&stus[i].scores[2]);

for(i=0;i<5;i++)
{
num=0;
for(j=0;j<3;j++)
num+=stus[i].scores[j];
stus[i].aver=num/3.0;
}

if((fp=fopen("stud.txt","wb+"))==NULL)
{
printf("cannot open the file.\n");
exit(0);
}
#ifdef FWRITE
for(i=0;i<5;i++)
{
if(fwrite(&stus[i],sizeof(struct student),1,fp)!=1)
printf("file write error\n");
}

printf("Read the data from the file.\n");
rewind(fp);
for(i=0;i<5;i++)
{
fread(&test[i],sizeof(struct student),1,fp);
printf("%d,%s,%d,%d,%d,%.2f\n",test[i].NUM,test[i].name,test[i].scores[0],
test[i].scores[1],test[i].scores[2],test[i].aver);
}
#else
for(i=0;i<5;i++)
fprintf(fp,"%d,%s,%d,%d,%d,%.2f\r\n",stus[i].NUM,stus[i].name,stus[i].scores[0],
stus[i].scores[1],stus[i].scores[2],stus[i].aver);
#endif
fclose(fp);
return 0;
}