c++实现简单的学生成绩管理系统

#include <iostream>
#include<string>
#include<vector>
#include<fstream>
#include<sstream>
#include<conio.h>

using namespace std;

class Student {
public:
string name;
string Id;
int grades;
void input();
void Readfile(istream &in);
void Writefile(ostream &out);
void print();
};

void Student::input() {
cout << "Please Input Student Name:";
cin >> name;
cout << "Please Input Student Id:";
cin >> Id;
cout << "Please Input Student Grades:";
cin >> grades;
}

void Student::Readfile(istream &in) {
in >> name >> Id >> grades;
}
void Student::Writefile(ostream &out) {
out << name << " " << Id << " " << grades << endl;
}

void Student::print() {
cout << "Student Name:" << name << endl
<< "Student Id:" << Id << endl
<< "Student Grades:" << grades << "\n" << endl;
}

class StudentManage {
public:
void add();
void broswer();
void search();
void menu();
void drop();
void modify();
vector<Student> sort();
void MWriteFile(vector<Student>);
private:
ofstream fout;
ifstream fin;
Student stu,stui;
vector<Student> stuVec;
Student& searchById(string &stuId);
Student& searchByName(string& n
4000
ame);
void swap(Student&, Student&);
};

void StudentManage::MWriteFile(vector<Student> wrtVec){
fout.open("test.txt");
for (auto & stuwrite : wrtVec)
stuwrite.Writefile(fout);
fout.close();
}

void StudentManage::add() {
stu.input();
fout.open("test.txt",ios::app);
stu.Writefile(fout);
fout.close();
}

void StudentManage::broswer() {
fin.open("test.txt");
stu.Readfile(fin);
while (!fin.eof()) {
stu.print();
stu.Readfile(fin);
}
fin.close();
}

Student& StudentManage::searchById(string &stuId) {
fin.open("test.txt");
stu.Readfile(fin);
while (!fin.eof())
if (stu.Id == stuId)
return stu;
fin.close();
}

Student& StudentManage::searchByName(string &stuName) {
fin.open("test.txt");
stu.Readfile(fin);
while (!fin.eof())
if (stu.name == stuName)
return stu;
fin.close();
}

void StudentManage::search() {
cout << "1.按姓名查找：" << endl
<< "2.按学号查找：" << endl
<< "请输入数字开始查找！";
int judge;
cin >> judge;
Student searchStu;
string searchCondition;
switch (judge)
{
case 1:
cout << "请输入学生姓名：";
cin >> searchCondition;
searchStu = searchByName(searchCondition);
searchStu.print();
break;
case 2:
cout << "请输入学生学号：";
cin >> searchCondition;
searchStu = searchById(searchCondition);
searchStu.print();
break;
default:
break;
}
}

void StudentManage::drop() {
cout << "1.按姓名删除" << endl
<< "2.按学号删除" << endl;
int judge;
fin.open("test.txt");
string dropCondition;
stu.Readfile(fin);
cin >> judge;
switch (judge)
{
case 1:
cout << "请输入要删除的学生姓名：";
cin >> dropCondition;
while (!fin.eof()) {
if (stu.name.compare(dropCondition) != 0) {
stuVec.push_back(stu);
stu.Readfile(fin);
}
else
stu.Readfile(fin);
}
break;
case 2:
cout << "请输入要删除的学生学号：";
cin >> dropCondition;
while (!fin.eof()) {
if (stu.name.compare(dropCondition) != 0) {
stuVec.push_back(stu);
stu.Readfile(fin);
}
else
stu.Readfile(fin);
}
break;
default:
break;
}
fin.close();
MWriteFile(stuVec);
cout << "删除成功" << endl;
}

void StudentManage::modify() {
int caseJudge;
string modifyCondition;
string line;
cout << "1.按姓名修改！" << endl
<< "2.按学号修改！" << endl;
fin.open("test.txt");
cin >> caseJudge;
switch (caseJudge)
{
case 1:
cout << "请输入要修改的学生姓名：";
cin >> modifyCondition;
while (getline(fin, line)) {                                        //运用getline();
istringstream record(line);                                   //讲记录绑定到刚读入的行
stu.Readfile(record);
//record >> stu.name >> stu.Id >> stu.grades;                 //或者直接读入流
if (stu.name == modifyCondition) {
stu.print();
cout << "确认修改？Y/N" << endl;
char judgeC;
cin >> judgeC;
switch (judgeC)
{
case 'Y':
stu.input();
stuVec.push_back(stu);
break;
default:
break;
}
}
else
stuVec.push_back(stu);
}
break;
case 2:
cout << "请输入要修改的学生学号：";
cin >> modifyCondition;
while (getline(fin, line)) {
istringstream record(line);
stu.Readfile(record);
//record >> stu.name >> stu.Id >> stu.grades;
if (stu.Id == modifyCondition) {
stu.print();
cout << "确认修改？Y/N" << endl;
char judgeC = getchar();
switch (judgeC)
{
case 'Y':
stu.input();
stuVec.push_back(stu);
break;
default:
break;
}
}
else
stuVec.push_back(stu);
}
break;
default:
break;
}
fin.close();
MWriteFile(stuVec);
cout << "修改成功！" << endl;
}

void StudentManage::swap(Student& stu1,Student& stu2) {
const Student temp = stu1;
stu1 = stu2;
stu2 = temp;
}

vector<Student> StudentManage::sort() {
cout << "即将按成绩对学生信息进行排序！" << endl;
fin.open("test.txt");
string line;
while (getline(fin, line)) {
istringstream record(line);
record >> stu.name >> stu.Id >> stu.grades;
stuVec.push_back(stu);
}
vector<Student>::size_type length = stuVec.size();
vector<Student>::size_type i,j;
bool change = true;
for (i = 1;i < length && change;++i) {
change = false;
for (j = 0;j < length - i;++j)
if (stuVec.at(j).grades > stuVec.at(j + 1).grades) {
swap(stuVec.at(j), stuVec.at(j + 1));
change = true;
}
}
fin.close();
for (auto test : stuVec) test.print();
return stuVec;
}

void StudentManage::menu() {
cout << "1.查看学生成绩信息" << endl
<< "2.增加学生成绩信息" << endl
<< "3.查找学生成绩信息" << endl
<< "4.删除学生成绩信息" << endl
<< "5.修改学生成绩信息" << endl
<< "6.排序学生成绩信息" << endl
<< "0.从本系统退出" << endl;
}

int main() {
bool quit = false;
StudentManage stum;
while (!quit) {
system("cls");
stum.menu();
cout << "请操作！" << endl;
int x;
cin >> x;
char judge;
switch (x)
{
case 1:
stum.broswer();
cout << "继续Y/N？";
cin >> judge;
if (judge == 'Y') break;
else { quit = true;break; }
case 2:
stum.add();
cout << "添加成功！" << endl;
cout << "继续Y/N？";
cin >> judge;
if (judge == 'Y') break;
else { quit = true;break; }
case 3:
stum.search();
cout << "继续Y/N？";
cin >> judge;
if (judge == 'Y') break;
else { quit = true;break; }
case 4:
stum.drop();
cout << "继续Y/N？";
cin >> judge;
if (judge == 'Y') break;
else { quit = true;break; }
case 5:
stum.modify();
stum.broswer();
cout << "继续Y/N？";
cin >> judge;
if (judge == 'Y') break;
else { quit = true;break; }
case 6:
stum.MWriteFile(stum.sort());
cout << "排序成功！" << endl;
cout << "继续Y/N？";
cin >> judge;
if (judge == 'Y') break;
else { quit = true;break; }
default:
quit = true;
break;
}
}
system("pause");
return 0;
}