基于链表实现的链式管理系统(C语言课设)

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
typedef struct Logincheck
{
    char account[1000];
    int choose;
}Login;
typedef struct Student
{
    char num[100];
    char name[20];
    int grade;
}Stu;
typedef struct ListNode
{
    Stu student;
    struct ListNode* next;
}ListNode;
//创建头节点
ListNode* createHead()
{
    ListNode* Head = (ListNode*)malloc(sizeof(ListNode));
    if (Head == NULL)
        return NULL;
    Head->next = NULL;
    return Head;
}
//创建节点
ListNode* createNode(Stu student)
{
    ListNode* pcur = (ListNode*)malloc(sizeof(ListNode));
    if (pcur == NULL)
        return NULL;
    pcur->student = student;
    pcur->next = NULL;
    return pcur;
}
//数据判重
int is_repeat(char* num)
{
    FILE* pf = fopen("学生数据.txt", "r");
    while (1)
    {
        Stu judgedata = { 0 };
        int judge = fscanf(pf, "%s%s%d", judgedata.num, judgedata.name, &judgedata.grade);
        if (!strcmp(judgedata.num, num))
            return 0;
        if (judge == EOF)
            return 1;
    }
}
//插入节点
void insertNode(ListNode* head, Stu student)
{
    ListNode* pcur = createNode(student);
    pcur->next = head->next;
    head->next = pcur;
}
//删除节点
void deleteNode(ListNode* head, char* num, FILE* pf)
{
    ListNode* prev = head;
    ListNode* pcur = head->next;
    while (pcur && strcmp(pcur->student.num, num))
    {
        if (!strcmp(pcur->student.num, num))
        {
            prev->next = pcur->next;
            free(pcur);
            return;
        }
        prev = prev->next;
        pcur = pcur->next;
    }
    if (!pcur)
    {
        printf("数据不存在,删除失败\n");
    }
    else
    {
        prev->next = pcur->next;
        FILE* pfs = fopen("数据备份.txt", "a");//备份删除的数据,方便后续找回
        fprintf(pfs, "%s\t%s\t%d\n", pcur->student.num, pcur->student.name, pcur->student.grade);
        fclose(pfs);
        free(pcur);
        pf = fopen("学生数据.txt", "w+");//打开一个临时文件,将删除后的数据拷贝在临时文件中,然后删除原文件
        pcur = head->next;
        while (pcur)
        {
            fprintf(pf, "%s\t%s\t%d\n", pcur->student.num, pcur->student.name, pcur->student.grade);
            pcur = pcur->next;
        }
        fclose(pf);
        printf("删除成功!\n");
    }
}
//打印链表
void printList(ListNode* head)
{
    ListNode* pcur = head->next;
    printf("编号\t姓名\t成绩\n");
    while (pcur)
    {
        printf("%s\t%s\t%d\n", pcur->student.num, pcur->student.name, pcur->student.grade);
        pcur = pcur->next;
    }
}
//查找节点
void seekNode(ListNode* head, char* num)
{
    ListNode* pcur = head->next;
    while (pcur && strcmp(pcur->student.num, num))
    {
        pcur = pcur->next;
    }
    if (pcur == NULL)
        printf("数据不存在\n");
    else
    {
        printf("编号姓名成绩\n");
        printf("%s\t%s\t%d\n", pcur->student.num, pcur->student.name, pcur->student.grade);
    }
}
//修改节点
void modifyNode(ListNode* head, char* num, Stu student)
{
    ListNode* pcur = head->next;
    while (pcur && strcmp(pcur->student.num, num))
    {
        pcur = pcur->next;
    }
    if (pcur == NULL)
        printf("要修改的数据不存在\n");
    else if (!is_repeat(pcur->student.num))
        printf("该编号已存在,请检查后重新修改!\n");
    else
    {
        pcur->student = student;
        FILE* pf = fopen("学生数据.txt", "w+");//将修改后的数据拷贝到文件中
        pcur = head->next;
        while (pcur)
        {
            fprintf(pf, "%s\t%s\t%d\n", pcur->student.num, pcur->student.name, pcur->student.grade);
            pcur = pcur->next;
        }
        printf("修改成功\n");
        fclose(pf);
    }
}
//登录界面
Login logInterface()
{
    Login log;
    printf("******************\n");
    printf("请输入账户密码\n");
    scanf("%s", log.account);
    printf("请选择登录或注册(0.登录 1.注册)\n");
    scanf("%d", &log.choose);
    printf("******************\n");
    return log;
}
//登录检测
char* loginCheck(Login log)
{
    FILE* pf = NULL;
    if (log.choose)//判断用户是要注册还是登录
    {
        pf = fopen("账户数据.txt", "a");
        fprintf(pf, "%s\n", log.account);
        printf("注册成功\n");
        fclose(pf);
        return "access";//注册成功,返回一个token
    }
    else if (log.choose == 0)
    {
        pf = fopen("账户数据.txt", "r");
        if (pf == NULL)
            printf("用户不存在!\n");
        else
        {
            while (1)//比对数据,成功返回一个token
            {
                char strcheck[1000] = { 0 };
                int judge = fscanf(pf, "%s", strcheck);
                if (!strcmp(strcheck, log.account))
                    return "access";
                if (judge == EOF)
                    break;
            }
            fclose(pf);
        }
    }
    return "fail";
}
//菜单
void menu()
{
    printf("******************\n");
    printf("0.退出程序\n");
    printf("1.浏览数据\n");
    printf("2.录入数据\n");
    printf("3.删除数据\n");
    printf("4.修改数据\n");
    printf("5.查找数据\n");
    printf("6.恢复备份\n");
    printf("7.按成绩排序\n");
    printf("******************\n");
}
//文件操作
//数据初始化
void initData(FILE* pf, ListNode* head)
{
    pf = fopen("学生数据.txt", "r");
    if (pf == NULL)
        printf("数据读取失败,请重试\n");
    else
    {
        ListNode* pcur = head->next;
        Stu student;
        while (fscanf(pf, "%s%s%d", student.num, student.name, &student.grade) != EOF)
        {
            insertNode(head, student);
        }
        fclose(pf);
    }
}
//数据保存
int saveData(FILE* pf, Stu student)
{
    pf = fopen("学生数据.txt", "a");
    if (pf == NULL)
        printf("数据录入失败\n");
    else if (!is_repeat(student.num))
        printf("该编号已存在,请检查后重新录入!\n");
    else
    {
        fprintf(pf, "%s\t%s\t%d\n", student.num, student.name, student.grade);//将录入的数据保存在文件中
        printf("已成功录入\n");
        return 1;
        fclose(pf);
    }
    return 0;
}
//恢复备份
void restoreBackup(FILE* pf, char* num)
{
    pf = fopen("学生数据.txt", "a");
    FILE* pfs = fopen("数据备份.txt", "r");
    if (pfs == NULL)
        printf("该目录下没有数据备份,无法恢复\n");
    else
    {
        Stu student;
        int flag = 1;
        while (fscanf(pfs, "%s%s%d", student.num, student.name, &student.grade) != EOF)
        {
            if (!strcmp(num, student.num))
            {
                fprintf(pf, "%s\t%s\t%d\n", student.num, student.name, student.grade);
                flag = 0;
            }
        }
        if (flag)
            printf("要恢复的数据不存在\n");
        else printf("已成功恢复备份!\n");
        fclose(pf);
        fclose(pfs);
    }
}
//对数据进行排序
void sortData(ListNode* head)
{
    for (ListNode* first = head->next; first != NULL; first = first->next)
    {
        for (ListNode* second = head->next; second != NULL; second = second->next)
        {
            if (second->next != NULL)
            {
                if (second->student.grade < second->next->student.grade)
                {
                    Stu student = second->student;
                    second->student = second->next->student;
                    second->next->student = student;
                }
            }
        }
    }
}
//获取用户操作
void keyDown(ListNode* head, FILE* pf)
{
    int input = 0;
    printf("请用户选择操作方式\n");
    scanf("%d", &input);
    Stu student;
    switch (input)
    {
    case 0:
        printf("程序正在退出\n");
        system("pause");
        exit(0);
        break;
    case 1:
        if (head->next == NULL)
            printf("暂时没有数据,无法浏览\n");
        else printList(head);
        break;
    case 2:
        printf("请用户输入学生信息:\n");
        scanf("%s %s %d", student.num, student.name, &student.grade);
        if (saveData(pf, student))
            insertNode(head, student);
        break;
    case 3:
        printf("请用户输入要删除的学生编号:");
        scanf("%s", student.num);
        deleteNode(head, student.num, pf);
        break;
    case 4:
        printf("请用户输入要修改的学生的编号:");
        char str[1000];
        scanf("%s", str);
        printf("请用户输入新的学生信息:\n");
        scanf("%s %s %d", student.num, student.name, &student.grade);
        modifyNode(head, str, student);
        break;
    case 5:
        printf("请用户输入要查找的学生编号:");
        scanf("%s", student.num);
        seekNode(head, student.num);
        break;
    case 6:
        printf("请输入要恢复的学生编号\n");
        char back[1000] = { 0 };
        scanf("%s", back);
        if (!is_repeat(back))
            printf("编号重复,请检查后重新输入\n");
        else
        {
            restoreBackup(pf, back);
            initData(pf, head);
            if (!remove("数据备份.txt"))
                printf("备份已删除\n");
        }
        break;
    case 7:
        sortData(head);
        printList(head);
        break;
    default:
        printf("非法操作,请重新输入!!!\n");
        break;
    }
}
int main()
{
    FILE* pf = NULL;
    while (1)
    {
        Login log = logInterface();
        char* check= loginCheck(log);
        if (!strcmp(check, "access"))//通过token判断是否存在这么一个用户
        {
            printf("登陆成功\n");
            break;
        }
        else printf("登录失败!请重试\n");
        system("pause");
        system("cls");
    }
    system("pause");
    system("cls");
    ListNode* pHead = createHead();
    initData(pf, pHead);
    while (1)
    {
        menu();
        keyDown(pHead, pf);
        system("pause");
        system("cls");
    }
    return 0;
}