文件操作（结构体写入失败）

/***
write.c
***/
#include<stdio.h>
#include<string.h>

struct student
{
    char name[10];
    int age;
};

int main()
{
    struct student st[10] = {0};
    int i;
    for(i = 0; i < 10; i++)
    {
        printf("please input name:\n");
        scanf("%s",st[i].name);
        printf("please input age:\n");
        scanf("%d",&st[i].age);
    }
    FILE *p = fopen("./a.txt","w");
    fwrite(st,sizeof(struct student),10,p);
    fclose(p);
}

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

struct student
{
    char name[100];
    int age;
};

int main()
{
    struct student st = {0};
    FILE *p = fopen("./a.txt","rb");
    while(!feof(p))
    {
        memset(&st,0,sizeof(struct student));
        fread(&st,sizeof(struct student),1,p);
        printf("name = %s , age = %d\n",st.name,st.age);
    }
    fclose(p);
    return 0;
}

read运行结果读取的数据不对。

/***

write.c

***/

#include<stdio.h>

#include<string.h>

 

struct student

{

       char name[10];

       int age;

};

 

int main()

{

       struct student st[10] = {0};

       int i;

       for(i = 0; i < 10; i++)

       {

              printf("please input name:\n");

              scanf("%s",st[i].name);

              printf("please input age:\n");

              scanf("%d",&st[i].age);

       }

       FILE *p = fopen("./a.txt","w");

       fwrite(st,sizeof(struct student),10,p);

       fclose(p);

}

 

以下程序读取成功：

// write.c
#include<stdio.h>
#include<string.h>

struct student 
{
    char name[100];
    int age;
};

int main()
{
    struct student st[3] = {0};
    int i;
    for(i = 0; i < 3; i++)
    {
        scanf("%s",st[i].name);
        scanf("%d",&st[i].age);
    }


    FILE * p = fopen("./c.txt","wb");
    fwrite(&st,sizeof(st),3,p);
    fclose(p);
    return 0;
}

//read.c
#include<stdio.h>
#include<string.h>

struct student
{
    char name[100];
    int age;
};

int main()
{
    struct student st[3] = {0};
    //FILE *p = fopen("./a.dat","rb");
    FILE *p = fopen("./c.txt","rb");
    int i;
    //while(!feof(p))
    for(i = 0; i < 3; i++)
    {
        //memset(&st,0,sizeof(struct student));
        fread(&st[i],sizeof(struct student),1,p);
        printf("name = %s , age = %d\n",st[i].name,st[i].age);
    }
    fclose(p);
    return 0;
}