Question

现在是newstaff.id，无法保存在文件中，文件中的fname和lname存储将更改位置

//struct
typedef struct
{
    char id[20],fname[50], lname[20],gender[3], address[30], department[30], phone[14], ic[16], email[30];
    date birthday;
    int age;
}staffInfo;
staffInfo newStaff;
//display
fscanf(stff, "%s %s %s %s %s %s %s %s %s",
            newStaff.id, newStaff.fname, newStaff.lname, &newStaff.gender, newStaff.department, newStaff.ic, newStaff.email, newStaff.phone, newStaff.address);

新问题

Answer 1

在文件中没有定义的分隔符（例如逗号或分号）来分隔字段，请尝试根据每个成员的宽度打印文件。 id的大小为20，因此请使用"%-*s"打印到文件。星号允许宽度作为变量，负号表示对正。
读取时，宽度是已知的，因此使用strncpy复制字符的宽度数，并使用trimtrailing删除尾随的空格。

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

#define ID 20
#define FNAME 50
#define LNAME 20
#define GENDER 3
#define DEPARTMENT 30
#define IC 16
#define EMAIL 30
#define PHONE 14
#define ADDRESS 30

struct staffinfo {
    char id[ID];
    char fname[FNAME];
    char lname[LNAME];
    char gender[GENDER];
    char department[DEPARTMENT];
    char ic[IC];
    char email[EMAIL];
    char phone[PHONE];
    char address[ADDRESS];
};

int fgetsline ( char *line, size_t len, FILE *fin) {
    do {
        if ( '\x01' == line[0]) {
            printf ( "\tToo many characters. Try again.\n\n");
        }
        if ( '\n' == line[0]) {
            printf ( "\tTry again.\n");
        }
        if ( fgets ( line, len, fin)) {
            if ( !strchr ( line, '\n')) {//no newline
                while ( !strchr ( line, '\n')) {//call until newline is found. clears input
                    if ( ! fgets ( line, len, fin)) {
                        fprintf ( stderr, "\nfgets EOF\n");
                        return 0;
                    }
                }
                line[0] = '\x01';//unlikely to be a valid character
            }
        }
        else {
            fprintf ( stderr, "\nfgets EOF\n");
            return 0;
        }
    } while ( '\x01' == line[0] || '\n' == line[0]);

    line[strcspn ( line, "\n")] = 0;//remove newline

    return 1;
}

void trimtrailing ( char *str) {
    char *temp = str;
    while ( str && *temp) {//not zero
        temp++;
    }
    if ( temp > str) {
        temp--;//character before zero
    }
    while ( temp > str && isspace ( *temp)) {
        *temp = 0;
        temp--;
    }
}

int main ( void) {
    struct staffinfo newStaff = { 0};

    printf ( "ID:");
    fflush ( stdout);//no newline in printf so force output
    if ( ! fgetsline ( newStaff.id, sizeof newStaff.id, stdin)) {
        exit ( EXIT_FAILURE);
    }
    printf ( "First name:");
    fflush ( stdout);//no newline in printf so force output
    if ( ! fgetsline ( newStaff.fname, sizeof newStaff.fname, stdin)) {
        exit ( EXIT_FAILURE);
    }
    printf ( "Last name:");
    fflush ( stdout);//no newline in printf so force output
    if ( ! fgetsline ( newStaff.lname, sizeof newStaff.lname, stdin)) {
        exit ( EXIT_FAILURE);
    }
    printf ( "Gender (M/F):");
    fflush ( stdout);//no newline in printf so force output
    if ( ! fgetsline ( newStaff.gender, sizeof newStaff.gender, stdin)) {
        exit ( EXIT_FAILURE);
    }
    printf ( "Deparment:");
    fflush ( stdout);//no newline in printf so force output
    if ( ! fgetsline ( newStaff.department, sizeof newStaff.department, stdin)) {
        exit ( EXIT_FAILURE);
    }
    printf ( "NRIC:");
    fflush ( stdout);//no newline in printf so force output
    if ( ! fgetsline ( newStaff.ic, sizeof newStaff.ic, stdin)) {
        exit ( EXIT_FAILURE);
    }
    printf ( "Email:");
    fflush ( stdout);//no newline in printf so force output
    if ( ! fgetsline ( newStaff.email, sizeof newStaff.email, stdin)) {
        exit ( EXIT_FAILURE);
    }
    printf ( "Mobile No.:");
    fflush ( stdout);//no newline in printf so force output
    if ( ! fgetsline ( newStaff.phone, sizeof newStaff.phone, stdin)) {
        exit ( EXIT_FAILURE);
    }
    printf ( "Address:");
    fflush ( stdout);//no newline in printf so force output
    if ( ! fgetsline ( newStaff.address, sizeof newStaff.address, stdin)) {
        exit ( EXIT_FAILURE);
    }

    FILE *pf = NULL;
    if ( NULL == ( pf = fopen ( "afile.txt", "a"))) {
        perror ( "afile.txt");
        exit ( EXIT_FAILURE);
    }
    fprintf ( pf, "%-*s", ID, newStaff.id);//print at least ID characters left justified
    fprintf ( pf, "%-*s", FNAME, newStaff.fname);
    fprintf ( pf, "%-*s", LNAME, newStaff.lname);
    fprintf ( pf, "%-*s", GENDER, newStaff.gender);
    fprintf ( pf, "%-*s", DEPARTMENT, newStaff.department);
    fprintf ( pf, "%-*s", IC, newStaff.ic);
    fprintf ( pf, "%-*s", EMAIL, newStaff.email);
    fprintf ( pf, "%-*s", PHONE, newStaff.phone);
    fprintf ( pf, "%-*s\n", ADDRESS, newStaff.address);

    fclose ( pf);

    if ( NULL == ( pf = fopen ( "afile.txt", "r"))) {
        perror ( "afile.txt");
        exit ( EXIT_FAILURE);
    }
    char line[1024] = "";
    char item[1024] = "";
    while ( fgetsline ( line, sizeof line, pf)) {
        int len = strlen ( line);
        int offset = 0;
        strncpy ( item, line + offset, ID - 1);
        item[ID - 1] = 0;
        trimtrailing ( item);
        printf ( "ID: %s\n", item);
        offset += ID;
        if ( offset >= len) {
            continue;
        }
        strncpy ( item, line + offset, FNAME - 1);
        item[FNAME - 1] = 0;
        trimtrailing ( item);
        printf ( "FNAME: %s\n", item);
        offset += FNAME;
        if ( offset >= len) {
            continue;
        }
        strncpy ( item, line + offset, LNAME - 1);
        item[LNAME - 1] = 0;
        trimtrailing ( item);
        printf ( "LNAME: %s\n", item);
        offset += LNAME;
        if ( offset >= len) {
            continue;
        }
        strncpy ( item, line + offset, GENDER - 1);
        item[GENDER - 1] = 0;
        trimtrailing ( item);
        printf ( "GENDER: %s\n", item);
        offset += GENDER;
        if ( offset >= len) {
            continue;
        }
        strncpy ( item, line + offset, DEPARTMENT - 1);
        item[DEPARTMENT - 1] = 0;
        trimtrailing ( item);
        printf ( "DEPARTMENT: %s\n", item);
        offset += DEPARTMENT;
        if ( offset >= len) {
            continue;
        }
        strncpy ( item, line + offset, IC - 1);
        item[IC - 1] = 0;
        trimtrailing ( item);
        printf ( "IC: %s\n", item);
        offset += IC;
        if ( offset >= len) {
            continue;
        }
        strncpy ( item, line + offset, EMAIL - 1);
        item[EMAIL - 1] = 0;
        trimtrailing ( item);
        printf ( "EMAIL: %s\n", item);
        offset += EMAIL;
        if ( offset >= len) {
            continue;
        }
        strncpy ( item, line + offset, PHONE - 1);
        item[PHONE - 1] = 0;
        trimtrailing ( item);
        printf ( "PHONE: %s\n", item);
        offset += PHONE;
        if ( offset >= len) {
            continue;
        }
        strncpy ( item, line + offset, ADDRESS - 1);
        item[ADDRESS - 1] = 0;
        trimtrailing ( item);
        printf ( "ADDRESS: %s\n", item);
    }
    fclose ( pf);
    return 0;
}

文本文件fscanf问题

1 个答案: