C语言实现文件存取信息的学生管理系统

C语言实现的一个使用单链表的学生管理系统，使用文件存储学生信息，结构体中包括学号、姓名和成绩，实现的功能有系统初始化（创建链表，读取文件中的信息到链表），添加学生记录，根据学号删除学生记录，根据学号修改学生信息（不能修改学号），根据学号查看学生信息，显示所有学生信息以及退出系统（将学生信息写入文件）。代码多有不足，请大家多多指教，有关于代码的问题可以私信我或者在评论区评论。

注意：该项目第一次运行，需要在项目根目录下新建一个StuNum.txt文件，在文件中写入0；

studentsystem.h

#include 
#include 
#define MaxSize 26
//声明文件指针
FILE *fp1,*fp2,*fp3,*fp4;
//链表节点，存放学生信息
typedef struct studentNode
{
 int no;
 char name[MaxSize];
 int score;
 struct studentNode *next;
}stuNode;
//链表头指针
stuNode* Head;
//初始化链表
stuNode* InitLinkList();
//新建结点
stuNode* ListInsert(int no,char name[MaxSize],int score);
//删除结点
int DeleteList(stuNode* head,int no);
//修改结点信息
int ChangeList(stuNode* head,int no,stuNode*);
//改变新修改结点位置
int Changeposition(stuNode* head,int no);
//查找结点
int SearchList(stuNode* head,int no);
//读文件
int Readfile(stuNode* head);
//写文件
int Writefile(stuNode* head);
//主界面
int MainMenu();
//添加
int Add(stuNode *head);
//删除
int Delete();
//修改
int Change();
//查找
int Search();
//显示学生信息
int Show(stuNode* head);
//系统初始化
int SystemInit();
//退出系统
int exitsystem();

studentsystem.c

#include 
#include 
#include "studentsystem.h"
//初始化链表,为链表头指针分配空间，读取学生记录个数
stuNode* InitLinkList()
{
    stuNode* head = (stuNode*)malloc(sizeof(stuNode));
    head->no = 16;
    strcpy(head->name,"BigData");
    fscanf(fp1,"%d",&head->score);
    head->next = NULL;
    return head;
}
//创建节点
stuNode* ListInsert(int no,char name[MaxSize],int score)
{
    stuNode* newnode = (stuNode*)malloc(sizeof(stuNode));
    newnode->no = no;
    strcpy(newnode->name,name);
    newnode->score = score;
    newnode->next = NULL;
    return newnode;
}
//从链表中删除结点
int DeleteList(stuNode* head,int no)
{
    stuNode *p,*q,*t;
    p = q = t = head->next;
    if (p->no == no)
    {
        head->next = p->next;
        head->score--;
        return 1;
    }
    while(p != NULL)
    {
        if(p->no == no)
        {
            while(q->next != p)
                q = q->next;
            q->next = p->next;
            head->score--;
            return 1;
        }
        p = p->next;
    }
    return 0;
}
//修改结点信息
int ChangeList(stuNode* head,int no,stuNode* t)
{
    stuNode* p,* q;
    p = head->next;
    q = head;
    while(p != NULL)
    {
        if(p->no == no)
        {
            t->next = p->next;
            while(q->next != p)
                q = q->next;
            q->next = t;
            Changeposition(head,no);
            return 1;
        }
        p = p->next;
    }
    return 0;
}
//对修改过的结点进行排序
int Changeposition(stuNode* head,int no)
{
    int k = 0;
    stuNode* p,* q,*t;
    p = t = head->next;
    q = head;
    while(t != NULL)
    {
        if(t->no == no)
        {
            printf("\n\t学号:%d",t->no);
            printf("\n\t姓名:%s",t->name);
            printf("\n\t成绩:%d\n",t->score);
            system("pause");
            break;
        }
        t = t->next;
    }
    while(q->next != t)
        q = q->next;
    while(t != head->next)
    {
        if (q->score < t->score)
        {
            q->next = t->next;
            while(p->next != q)
                p = p->next;
            t->next = q;
            p->next = t;
            q = p;
            k = 1;
        }
        else
            break;
    }
    if(k == 0)
    {
        p = t->next;
        while(p != NULL)
        {
            if (p->score > t->score)
            {
                t->next = p->next;
                while(q->next != t)
                    q = q->next;
                p->next = t;
                q->next = p;
                p = t->next;
            }
            else
                break;
        }
    }
    return 0;
}
//查找链表结点
int SearchList(stuNode* head,int no)
{
    stuNode* p = head->next;
    while(p != NULL)
    {
        if(p->no == no)
        {
            printf("\n\t学号:%d",p->no);
            printf("\n\t姓名:%s",p->name);
            printf("\n\t成绩:%d\n",p->score);
            return 1;
        }
        p = p->next;
    }
    return 0;
}
//读文件函数，从文件中读取学生信息到链表
int Readfile(stuNode* head)
{
    int i = 0;
    if(head->score != 0)
    {
        stuNode *q = head;
        for(i = 0;i < head->score; i++)
        {
            stuNode *p = (stuNode*)malloc(sizeof(stuNode));
            //fread(p,sizeof(stuNode),1,fp3);
            fscanf(fp3,"%d %s %d",&p->no,p->name,&p->score);
            p->next = NULL;
            q->next = p;
            q = q->next;
        }
    }
    return 0;
}
//写文件函数，将学生信息从链表写入文件
int Writefile(stuNode* head)
{
    fprintf(fp2,"%d",head->score);
    stuNode* p = head->next;
    while(p != NULL)
    {
        fprintf(fp4,"%d %s %d\n",p->no,p->name,p->score);
        p = p->next;
    }
    return 0;
}
//主界面，显示操作菜单，输入操作数选择操作
int MainMenu()
{
 int i;
 printf("\t\tWelcome to the System of Student Management\n");
 printf("\n\t\t\t1.Add student's information\n");
 printf("\n\t\t\t2.Delete student's information\n");
 printf("\n\t\t\t3.Change student's information\n");
 printf("\n\t\t\t4.Search student's information\n");
 printf("\n\t\t\t5.Show student's information\n");
 printf("\n\t\t\t6.exit system\n\n");
 printf("\tPlease input you choose:");
 scanf("%d",&i);
 switch(i)
 {
  case 1:
   system("cls");
   Add(Head);
   break;
  case 2:
   system("cls");
   Delete();
   break;
  case 3:
   system("cls");
   Change();
   break;
  case 4:
   system("cls");
   Search();
   break;
  case 5:
   system("cls");
   Show(Head);
   break;
  case 6:
   system("cls");
   exitsystem();//
   break;
  default:
   break;
 }
 return 0;
}
//添加学生信息
int Add(stuNode *head)
{
    int no,score;
    char name[MaxSize];
    stuNode* p = head->next;
    stuNode* q = head->next;
    stuNode* n;
    printf("\n\tPlease input student's NO:");
    scanf("%d",&no);
    printf("\n\tPlease input student's name:");
    scanf("%s",name);
    printf("\n\tPlease input student's score:");
    scanf("%d",&score);
    n = ListInsert(no,name,score);
    if (p == NULL) //链表判空
        head->next = n;
    else
    {
        while(p != NULL )
        {
            if(p->score <= score)
                break;
            p = p->next;
        }
        if(p != NULL)
        {
            if(p == q)
            {
                n->next = p;
                head->next = n;
            }
            else
            {
                while(q->next != p)
                {
                    q = q->next;
                }
                n->next = p;
                q->next = n;
            }
        }
        else
        {
            while(q->next != NULL)
                q = q->next;
            q->next = n;
        }
    }
    head->score++;
    return 0;
}
//删除学生信息
int Delete()
{
    int i,n;
    printf("\tPlease input the No of student's which you want delete:");
    scanf("%d",&i);
    n = DeleteList(Head,i);
    if(n)
    {
        printf("\n\t删除成功\n");
        system("pause");
        return 0;
    }
    printf("\n\t没有找到该学生的记录\n");
    system("pause");
    return 0;
}
//修改学生信息
int Change()
{
    int i,x;
    stuNode *n = (stuNode*)malloc(sizeof(stuNode));
    printf("请输入要修改的学生的学号:");
    scanf("%d",&i);
    printf("请输入修改后学生的信息\n");
    n->no = i;
    printf("请输入学生姓名:");
    scanf("%s",n->name);
    printf("请输入学生成绩:");
    scanf("%d",&n->score);
    n->next = NULL;
    x = ChangeList(Head,i,n);
    if(x)
    {
        printf("\n\t修改成功\n");
        system("pause");
        return 0;
    }
    printf("\n\t没有找到该学生的记录\n");
    system("pause");
    return 0;
}
//查找学生信息
int Search()
{
    int n,no;
    printf("请输入要查询的学生学号:");
    scanf("%d",&no);
    n = SearchList(Head,no);
    if(n == 0)
        printf("\n\t没有找到该学生的记录\n");
    system("pause");
    return 0;
}
//显示所有学生信息
int Show(stuNode* head)
{
    printf("\t年级:%d届\t班级:%s\t人数:%d\n\n",head->no,head->name,head->score);
    stuNode* p = head->next;
    while(p != NULL)
    {
        printf("%d\t%s\t%d\n\n",p->no,p->name,p->score);
        p = p->next;
    }
    printf("以上是全部学生信息\n");
    system("pause");
    return 0;
}
//系统初始化,打开文件，初始化链表头指针，读取学生信息
int SystemInit()
{
    fp1 = fopen("StuNum.txt","r+");
    fp2 = fopen("StuNu.txt","w+");
 fp3 = fopen("StuInformation.txt","r+");
 fp4 = fopen("StuIn.txt","w+");
 Head = InitLinkList();
 Readfile(Head);
    return 0;
}
//退出系统函数,存储信息，关闭文件,释放链表空间并退出程序
int exitsystem()
{
    Writefile(Head);
 fclose(fp1);
 fclose(fp2);
 remove("StuNum.txt");
 rename("StuNu.txt","StuNum.txt");
 fclose(fp3);
 fclose(fp4);
 remove("StuInformation.txt");
 rename("StuIn.txt","StuInformation.txt");
 exit(0);
}

main.c

#include 
#include 
#include "studentsystem.h"
int main()
{
 SystemInit();
 while(1)
 {
        system("cls");
  MainMenu();
 }
 return 0;
}