从文件读取到 LinkedList C 时，最终字段为 NULL

Question

所以我正在从一个文件读入一个链表。除了最后一个字段 "email" 只是读取 null 之外，一切都正常。有人有什么想法吗？

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


#define ID_LENGTH 25
#define NAME_LENGTH 25
#define address_LENGTH 25
#define department_LENGTH 25
#define joinDate_LENGTH 25
#define email_LENGTH 30

//Create employee Structure
typedef struct employee{
    char* ID;
    char* name;
    char* address;
    char* department;
    char* joinDate;
    double salary;
    char* email;
    struct employee *next;
}employee;

//Declare Function Prototypes
employee* new_employee(char*, char*, char*, char*, char*, double, char*);
employee* insert_by_employee(employee*, employee*);
void print_list(employee*);


int main() {

    FILE *in;
    char* ID = (char*)malloc(sizeof(char*) * ID_LENGTH);
    char* name = (char*)malloc(sizeof(char*) * NAME_LENGTH);
    char* department = (char*)malloc(sizeof(char*) * department_LENGTH);
    char* address = (char*)malloc(sizeof(char*) * address_LENGTH);
    char* joinDate = (char*)malloc(sizeof(char*) * joinDate_LENGTH);
    double salary = 0;
    char* email = (char*)malloc(sizeof(char*) * email_LENGTH);


    if ((in = fopen("Employees.txt", "r")) == NULL) //Did the file successfully open?
    {
        printf("The input file failed to open.\n");
        printf("Program cannot continue. Exiting. . .\n");
        return 1; //Exit Program
    }


    //2. ------Linked List Operations------
    employee* head = NULL; //Create Empty Linked List
    employee* current = NULL;



    while (!feof(in)) //Check for file end
    {
        //Read first data value to kickstart.
        if (fscanf(in, "%s %s %s %s %s %d %s", ID, name, department, address, joinDate, &salary, email) == EOF) {
            break;
        }

        employee* hold = new_employee(ID, name, department, address, joinDate, salary, email);
        head = insert_by_employee(head, hold);


    }

    //3. ------Print the new List------
    print_list(head);
    system("pause");
    return 1; //Exit Success
}
employee* new_employee(char* id, char* name, char* department, char* address, char* joinDate, double salary, char* email) {

    //Create new employee and malloc space
    employee* new = (employee*)malloc(sizeof(struct employee));
    new->ID = (char*)malloc(sizeof(char) * ID_LENGTH);
    new->name = (char*)malloc(sizeof(char) * NAME_LENGTH);
    new->department = (char*)malloc(sizeof(char) * department_LENGTH);
    new->address = (char*)malloc(sizeof(char) * address_LENGTH);
    new->joinDate = (char*)malloc(sizeof(char) * joinDate_LENGTH);
    new->email = (char*)malloc(sizeof(char) * email_LENGTH);



    //Set data
    strcpy(new->ID, id);
    strcpy(new->name, name);
    strcpy(new->department, department);
    strcpy(new->address, address);
    strcpy(new->joinDate, joinDate);
    new->salary = salary;
    strcpy(new->email, email);
    //Retun a pointer to the node
    return new;

}

//Inserts new node into an alphabetically sorted linked list.
employee* insert_by_employee(employee* head, employee* new)
{
    employee* current = NULL;
    current = head;
    if (current == NULL || strcmp(current->name, new->name) > 0)
    {
        new->next = current;
        return new;
    }
    else {

        while (current->next != NULL && strcmp(current->next->name, new->name) < 0)
        {

            current = current->next;
        }
    }
    new->next = current->next;
    current->next = new;
    return head;

}
void print_list(employee* head)
{
    employee* current;
    current = head;
    char i[] = "Employee ID";
    char n[] = "Name";
    char a[] = "Address";
    char d[] = "Department";
    char jd[] = "Join Date";
    char s[] = "Salary";
    char em[] = "Email";


    //Header
    printf("\n\n|%15s | %15s | %15s | %15s | %15s| %15s | %15s|\n", i, n, a, d, jd, s, em);
    printf("--------------------------------------------------------------------------------------------------------------------------------------------\n");


    while (current != NULL)
    {
        printf("|%15s | %15s | %15s |%15s | %15s | %15d| %15s\n", current->ID, current->name, current->address, current->department, current->joinDate, current->salary, current->email);
        current = current->next;
    }
    printf("-------------------------------------------------------------------------------------------------------------------------------------------\n");


    return;
}

这是向链表输入数据的示例文件

EMP1 Martin Clare Computer 06/06/1996 60000 hannanmartin@gmail.com
EMP2 John Galway Accounting 05/05/1995 50000 johnemp@gmail.com
EMP3 Kevin Kilkenny Computer 04/04/1994 34000 kevinemp@gmail.com
EMP4 Kim Sligo Sales 03/03/1993 65000 kimemp@gmail.com
EMP5 Keith Ballina Accounting 02/02/1992 53200 keithemp@gmail.com
EMP6 Tim Dublin Sales 01/01/1991 23000 timemp@gmail.com
EMP7 Andy Chicago Computer 07/07/1990 10000 andyemp@gmail.com

Answer 1

薪水是双精度而不是整数。但是您在 scanf 和 printf 调用中一直使用 %d 。将 %lf 用于双打，或将 salary 更改为整数。

从文件读取到 LinkedList C 时，最终字段为 NULL

Final field is NULL when reading from file to a LinkedList C

c

file-io

linked-list