自己用C语言写的学生管理系统,数据存入文件。

#include <stdio.h>
#include <stdlib.h>
#include "common.h"/*
函数：Show
功能：显示菜单
注意：使用后记得清屏
*/
void Show()
{system("cls");      //清屏printf("\t学生信息管理系统\r\n");printf("1.增加学生信息  2.删除学生信息    3.修改学生信息\r\n");printf("4.查询学生信息  5.统计学生信息    6.显示学生数据\r\n");printf("7.磁盘整理     8.退出\r\n");printf("please close 1-8:");
}

#define _CRT_SECURE_NO_WARNINGS
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include "common.h"/*
函数：Add
功能：增加学生信息
注意：不可以无限制的增加
*/
void Add()
{int i = 0;int nCount = 0;char aryInput[2] = { 0 };FILE *pf = NULL;if ((pf = fopen("data.txt", "a+")) == NULL){printf("不能打开！\r\n");}while (!feof(pf)){if (fread(&Stu[nCount], STU_LENGTH, 1, pf) == 1){nCount++;       //统计当前记录条数}}fclose(pf);if (nCount == 0){printf("没有记录,请开始添加：\r\n");}else{system("cls");ShowData();}if ((pf = fopen("data.txt", "wb")) == NULL){printf("不能打开！\r\n");}for (i = 0; i < nCount; i++){fwrite(&Stu[i], STU_LENGTH, 1, pf);      //写入文件}printf("是否要添加学生信息(y/n):");scanf("%s", aryInput);while (strcmp(aryInput, "Y") == 0 || strcmp(aryInput, "y") == 0)    //判断是否要录入新信息{printf("请输入学号:");scanf("%d", &Stu[nCount].nId);for (i = 0; i < nCount; i++){if (Stu[i].nId == Stu[nCount].nId){printf("这个学号已经存在,请按任意键继续!");}}printf("请输入姓名:");scanf("%s", Stu[nCount].szName);printf("请输入电话号码:");scanf("%d", &Stu[nCount].nTel);printf("请输入C语言成绩:");scanf("%lf", &Stu[nCount].dblCGrade);printf("请输入生日(年-月-日):");scanf("%d-%d-%d", &Stu[nCount].Bir.nYear, &Stu[nCount].Bir.nMonth, &Stu[nCount].Bir.nDay);Stu[i].isDel = 1;if (fwrite(&Stu[nCount], STU_LENGTH, 1, pf) != 1)   //将新录入的信息写入文件{printf("不能保存!");}else{printf("%s同学已经保存!\n", Stu[nCount].szName);nCount++;}printf("是否继续(y/n):");scanf("%s", aryInput);}fclose(pf);
}/*
函数：Del
功能：删除学生信息
注意：是以序号来删除的
*/
void Del()
{int i = 0;int nIndex = 0;int nCount = 0;int nDelNumber = 0;//删除的序号int nAge = 0;char aryInput[2] = { 0 };FILE *pf = NULL;if ((pf = fopen("data.txt", "r+")) == NULL){printf("不能打开\r\n");}while (!feof(pf)){if (fread(&Stu[nCount], STU_LENGTH, 1, pf) == 1){nCount++;}}fclose(pf);if (nCount == 0){printf("没有记录\r\n");}ShowData();printf("请输入要删除的学号:");scanf("%d", &nDelNumber);if (Stu[i].isDel == 0){printf("此数据已被删除,请重新输入\r\n");system("pause");}else{for (i = 0; i < nCount; i++){if (nDelNumber == Stu[i].nId){printf("找到这个学生,是否删除(y/n)");scanf("%s", aryInput);if (strcmp(aryInput, "Y") == 0 || strcmp(aryInput, "y") == 0)//判断是否要进行删除{Stu[i].isDel = 0;}if ((pf = fopen("data.txt", "wb")) == NULL){printf("不能打开\r\n");}for (nIndex = 0; nIndex < nCount; nIndex++)//将更改后的记录写入文件中{if (fwrite(&Stu[nIndex], STU_LENGTH, 1, pf) != 1){printf("不能保存!\r\n");}}fclose(pf);printf("删除成功!\r\n");system("pause");}}for (i = 0; i < nCount; i++){if (Stu[i].isDel != 0){printf("●");}else if (Stu[i].isDel == 0){printf("○");}}system("pause");}
}/*
函数：Mod
功能：修改学生的信息
注意：修改注意长度
*/
void Mod()
{int i = 0;int j = 0;int nCount = 0;int nModInput = 0;FILE *pf = NULL;if ((pf = fopen("data.txt", "r+")) == NULL){printf("不能打开\r\n");}while (!feof(pf)){if (fread(&Stu[nCount], STU_LENGTH, 1, pf) == 1){nCount++;}}if (nCount == 0){printf("没有记录！\r\n");fclose(pf);}ShowData();printf("请输入要修改的学号:");scanf("%d", &nModInput);for (i = 0; i < nCount; i++){if (nModInput == Stu[i].nId)//判断是否有修改的信息{printf("请输入修改后的姓名:");scanf("%s", Stu[i].szName);printf("请输入修改后的电话号码:");scanf("%s", &Stu[i].nTel);printf("请输入修改后的C语言成绩:");scanf("%lf", &Stu[i].dblCGrade);printf("修改成功!");system("pause");if ((pf = fopen("data.txt", "wb")) == NULL){printf("不能打开\r\n");}for (j = 0; j < nCount; j++)/*将新修改的信息写入文件中*/{if (fwrite(&Stu[j], STU_LENGTH, 1, pf) != 1){printf("不能保存!\r\n");}}fclose(pf);}}printf("没有找到要修改的信息！\n");
}/*
函数：Search
功能：查找学生的信息
注意：可根据姓名学号等查找
*/
void Search()
{int i = 0;int j = 0;int nCount = 0;int nAge = 0;     //计算出来的年龄int nSearchInput = 0;  //输入的1234int nInputId = 0;   //输入的学号int nInputTel = 0;  //输入的号码double dblInputGrade = 0.0f;     //输入的成绩char aryInput[2] = { 0 };char szInputName[15] = { 0 };  //输入的姓名FILE *pf = NULL;if ((pf = fopen("data.txt", "rb")) == NULL){printf("不能打开\r\n");}while (!feof(pf)){if (fread(&Stu[nCount], STU_LENGTH, 1, pf) == 1){nCount++;}}fclose(pf);if (nCount == 0){printf("没有记录!\r\n");}printf("请输入要查找的方式1.学号 2.姓名 3.成绩 4.号码:\r\n");scanf("%d", &nSearchInput);switch (nSearchInput){case 1:printf("请输入要查找的学号：\r\n");scanf("%d", &nInputId);for (j = 0; j < nCount; j++){if (nInputId == Stu[j].nId && Stu[j].isDel != 0){printf("学号           姓名           电话号码       C语言成绩     年龄\t\r\n");nAge = 2018 - Stu[j].Bir.nYear;printf("%-15d%-15s%-15d%-15.1lf%-15d\r\n", Stu[j].nId, Stu[j].szName,Stu[j].nTel, Stu[j].dblCGrade, nAge);break;}else if (nInputId == Stu[j].nId && Stu[j].isDel == 0){printf("此条数据已被删除\r\n");}}system("pause");break;case 2:printf("请输入要查找的姓名：\r\n");scanf("%s", szInputName);printf("学号           姓名           电话号码       C语言成绩     年龄\t\r\n");for (j = 0; j < nCount; j++){if (strcmp(szInputName, Stu[j].szName) == 0 && Stu[j].isDel != 0){nAge = 2018 - Stu[j].Bir.nYear;printf("%-15d%-15s%-15d%-15.1lf%-15d\r\n", Stu[j].nId, Stu[j].szName,Stu[j].nTel, Stu[j].dblCGrade, nAge);break;}else if (strcmp(szInputName, Stu[j].szName) == 0 && Stu[j].isDel == 0){printf("此条数据已被删除\r\n");}}system("pause");break;case 3:printf("请输入要查找的成绩：\r\n");scanf("%lf", &dblInputGrade);for (j = 0; j < nCount; j++){if (dblInputGrade == Stu[j].dblCGrade && Stu[j].isDel != 0){nAge = 2018 - Stu[j].Bir.nYear;printf("学号           姓名           电话号码       C语言成绩     年龄\t\r\n");printf("%-15d%-15s%-15d%-15.1lf%-15d\r\n", Stu[j].nId, Stu[j].szName,Stu[j].nTel, Stu[j].dblCGrade, nAge);break;}else if (dblInputGrade == Stu[j].dblCGrade && Stu[j].isDel == 0){printf("此条数据已被删除\r\n");}}system("pause");break;case 4:printf("请输入要查找的号码：\r\n");scanf("%d", &nInputTel);printf("学号           姓名           电话号码       C语言成绩     年龄\t\r\n");for (j = 0; j < nCount; j++){if (nInputTel == Stu[j].nTel && Stu[j].isDel != 0){nAge = 2018 - Stu[j].Bir.nYear;printf("%-15d%-15s%-15d%-15.1lf%-15d\r\n", Stu[j].nId, Stu[j].szName,Stu[j].nTel, Stu[j].dblCGrade, nAge);break;}else if (nInputTel == Stu[j].nTel && Stu[j].isDel == 0){printf("此条数据已被删除\r\n");}}}system("pause");}/*
函数：Statis
功能：统计学生的信息
注意：只可以统计出学生的最高最低平均分
*/
void Statis()
{int i = 0;int j = 0;int nCount = 0;double dblSum = 0.0;double dblValue = 0.0;double dblMaxSouce = 0.0;double dblMinSouce = 0.0;FILE *pf = NULL;if ((pf = fopen("data.txt", "r+")) == NULL){printf("不能打开\r\n");}while (!feof(pf)){if (fread(&Stu[nCount], STU_LENGTH, 1, pf) == 1){nCount++;//统计记录学生个数}}if (nCount == 0){printf("没有记录!\r\n");fclose(pf);}/*计算平均分*/for (i = 0; i < nCount; i++) //统计的时候,做个判断,如果被删除了,就不做统计{if (Stu[i].isDel != 0){dblSum += Stu[i].dblCGrade;}}for (i = 0; i < nCount; i++) //如果那条数据被删除,总长度自减{if (Stu[i].isDel == 0){nCount--;}}dblValue = dblSum / nCount;printf("平均分为:%5.1lf\r\n", dblValue);dblMaxSouce = Stu[0].dblCGrade;dblMinSouce = Stu[0].dblCGrade;for (j = 1; j < nCount; j++){if (Stu[j].dblCGrade > dblMaxSouce){dblMaxSouce = Stu[j].dblCGrade;}else if (Stu[j].dblCGrade < dblMinSouce){dblMinSouce = Stu[j].dblCGrade;}}printf("最高分为:%5.1lf\r\n", dblMaxSouce);printf("最低分为:%5.1lf\r\n", dblMinSouce);system("pause");fclose(pf);
}/*
函数：ShowData
功能：显示已经输入的信息
注意：断电也可以显示
*/
void ShowData()
{int i = 0;int nCount = 0;int nAge = 0;FILE *pf = NULL;pf = fopen("data.txt", "rb");while (!feof(pf)){if (fread(&Stu[nCount], STU_LENGTH, 1, pf) == 1){nCount++;}}fclose(pf);printf("学号           姓名           电话号码       C语言成绩      年龄       是否被删除(1否/0是)\t\r\n");for (i = 0; i < nCount; i++){nAge = 2018 - Stu[i].Bir.nYear;printf("%-15d%-15s%-15d%-15.1lf%-15d%-15d\r\n", Stu[i].nId, Stu[i].szName,Stu[i].nTel, Stu[i].dblCGrade, nAge, Stu[i].isDel);}Fifure();system("pause");
}/*
函数：Fifure
功能：显示磁盘分布图
注意：空心代表无,实心代表有
*/
void Fifure()
{int i = 0;int nCount = 0;int nAge = 0;FILE *pf = NULL;pf = fopen("data.txt", "rb");while (!feof(pf)){if (fread(&Stu[nCount], STU_LENGTH, 1, pf) == 1){nCount++;}}fclose(pf);for (i = 0; i < nCount; i++){if (Stu[i].isDel != 0){printf("●");}else if (Stu[i].isDel == 0){printf("○");}}
}/*
函数：Finish
功能：磁盘整理
注意：定长
*/
void Finish()
{int i = 0;int j = 0;int nCount = 0;int nIndex = 0;//空心圈的总数FILE *pf = NULL;if ((pf = fopen("data.txt", "rb")) == NULL){printf("不能打开\r\n");}while (!feof(pf)){if (fread(&Stu[nCount], STU_LENGTH, 1, pf) == 1){nCount++;}}fclose(pf);for (i = 0; i < nCount; i++){if (Stu[i].isDel == 0){nIndex++;}}int nCurLength = nCount;for (i = 0; i < nIndex; i++){for (j = 0; j < nCount; j++){if (Stu[j].isDel == 0){Stu[j] = Stu[j + 1];}}nCurLength--;}printf("整理成功\r\n");if ((pf = fopen("data.txt", "wb")) == NULL){printf("不能打开\r\n");}for (j = 0; j < nCurLength; j++){if (fwrite(&Stu[j], STU_LENGTH, 1, pf) != 1){printf("不能保存!\r\n");}}fclose(pf);for (i = 0; i < nCount; i++){if (Stu[i].isDel != 0){printf("●");}}system("pause");
}

/************************************************************
Copyright (C), 2017-2018, Tech. Co., Ltd.
FileName: File_StuManagement.c
Description: 完成对学生信息的增加,删除,修改,查找,统计,显示,磁盘整理功能
Version: V1.0
Function List: common.h
David 17/10/05 1.0
***********************************************************/#include <stdio.h>
#include <stdlib.h>
#include "common.h"/*
函数：main
功能：查询
*/
int main()
{int nInput = 0;Show();scanf("%d", &nInput);while (nInput){switch (nInput){case 1:Add();break;case 2:Del();break;case 3:Mod();break;case 4:Search();break;case 5:Statis();break;case 6:ShowData();break;case 7:Finish();break;case 8:break;default:break;}system("cls");Show();             //再显示菜单界面scanf("%d", &nInput);}return 0;
}