c - 如何将值传递给结构变量然后将结构写入文件？

Question

如何将值传递给结构变量我试图从用户那里获取员工信息然后将它们写入文件中，但是segmentation fault在输入员工姓名后我得到了一个。这是我的代码。

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

struct record_em{
    int id;
    char name[20];
    int salary;
    int age;
};

int main( void )
{
    struct record_em employee;
    FILE *fp;
    int id, salary, age;
    char name[20];
    int n=1;

    fp = fopen("empRecord.dat","a");
    while(n==1){
        printf("\nEnter Employee ID\n");
        scanf("%d",&id);
        employee.id=id;
        printf("\nEnter Employee Name\n");
        scanf("%s",name);
        employee.name=name;
        printf("\nEnter Employee Salary\n");
        scanf("%d",&salary);
        employee.salary=salary;
        printf("\nEnter Employee Age\n");
        scanf("%d",&age);
        employee.age=age;
        fwrite(&employee,sizeof(employee),1,fp);
        printf("Enter 1 to add new record \n");
        scanf("%d",&n);
    }

    fclose(fp);

    return 0;
    }

输出（取自评论）：

Fatmahs-MacBook-Air:~ fatmah$ gcc -o em em.c
Fatmahs-MacBook-Air:~ fatmah$ ./em
输入员工编号
88
输入员工姓名
你
分段错误：11

score 6 · Accepted Answer

改变

scanf("%s",name);
employee.name=name;

到

scanf("%s",name);
strcpy(employee.name, name);

更好的是，正如 Dukeling & hmjd 所建议的那样

scanf("%19s", employee.name);

score 3 · Accepted Answer

这是一个主要问题：

scanf("%s",name);
employee.name=name;

该成员name是一个数组，您不能分配给它。而是使用复制strcpy到它。

score 0 · Accepted Answer

创建一个 typedef 结构record_t以使内容更短且更易于理解。

typedef struct {
    int id;
    char name[20];
    int salary;
    int age;
} record_t;

首先创建文件并格式化。

void file2Creator( FILE *fp )
{
    int i; // Counter to create the file.
    record_t data = { 0, "", 0, 0 }; // A blank example to format the file.

    /* You will create 100 consecutive records*/
    for( i = 1; i <= 100; i++ ){
        fwrite( &data, sizeof( record_t ), 1, fp );
    }

    fclose( fp ); // You can close the file here or later however you need.  
}

编写函数来填充文件。

void fillFile( FILE *fp )
{
    int position;
    record_t data = { 0, "", 0, 0 };


    printf( "Enter the position to fill (1-100) 0 to finish:\n?" );
    scanf( "%d", &position );

    while( position != 0 ){
        printf( "Enter the id, name, and the two other values (integers):\n?" );
        fscanf( stdin, "%d%s%d%d", &data.id, data.name, data.salary, data.age );

        /* You have to seek the pointer. */
        fseek( fp, ( position - 1 ) * sizeof( record_t ), SEEK_SET );
        fwrite( &data, sizeof( record_t ), 1, fp );
        printf( "Enter a new position (1-100) 0 to finish:\n?" );
        scanf( "%d", &position );
    }

    fclose( fPtr ); //You can close the file or not, depends in what you need.
}

您可以将其用作参考比较和检查两个文件中的列

c - 如何将值传递给结构变量然后将结构写入文件？

3 回答 3

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