Question

我有一个学生的结构，写入一个文件所有我想要的是使用任何方法从文件的值初始化数组，目的是将struct值放入数组以帮助排序过程代码给我打孔任何想法如何实现它

#include <stdio.h>
#include <string.h>
#include <conio.h>
#include <stdlib.h>
#include <windows.h>
struct student
 {
  char  id[5];
  char  name[30];
  int   term;
  float gpa;
  char  grade;
 };

struct student stu;

typedef struct student stud;


int main ()
{
FILE *fp;
fp = fopen("record.txt","ab+");
char nextChar = getc(fp);
int numCharacters = 0;

while (nextChar != EOF)
{
    numCharacters++;
    nextChar = getc(fp);
}
//////// detect number of characters ////////

int chunck = numCharacters/sizeof(stu);

stud *arr = (stud *)malloc(chunck);

/*//problem comes next ...
// intial the array of students with records from file
while(fread(&stu,sizeof(stu),1,fp) == 1)
{ 
  for(d=0;d<chunck;d++)
  {
   arr[d].id=stu.id;
   arr[d].name=stu.name;
   arr[d].term=stu.term;
   arr[d].gpa=stu.gpa;
  }     
}*/

return 0;
}

Answer 1

在您阅读和初始化arr struct之前，需要再次将光标放在文件的开头。

如评论中所述----＆gt;使用fseek或rewind

使用fread的struct的初始数组

1 个答案: