C++大作业——学生选课系统优化版
发布时间：2024年01月03日
C++大作业——学生选课系统优化版
前言
本文是对本人之前写过的一个学生选课系统的优化，整体上的逻辑是和我上一篇博客一样的（链接在此：https://blog.csdn.net/weixin_73870552/article/details/135298985?spm=1001.2014.3001.5501）。本文将具体介绍优化的部分，而不对基本的实现做过多阐述。
1.学生类和课程类的实现
课程类：
class Course
{
// 输入输出流重载
friend ostream& operator<<(ostream& out, const Course& c);
friend fstream& operator<<(fstream& fout, const Course& c);
// friend istream& operator>>(istream& in, Course& c); 这个重载不好实现，因为要查重
friend fstream& operator>>(fstream& fin, Course& c);
friend ostream& operator<<(ostream& out, const Student& s);
public:
// 构造函数初始化
Course()
: _id("None")
, _name("None")
, _type(0)
, _hour(0)
, _credir(0)
, _count(0)
{}
// 相关接口
const string c_id() { return _id; } // 编号的接口
const string c_name() { return _name; } // 名字的接口
int& c_count() { return _count; } // 选课人数的接口
const bool c_type() { return _type; } // 类型接口
// 文件操作
void Write(vector<Course>& cour, int n) {} // 向文件写入数据
int Read(vector<Course>& cour) {} // 从文件读取数据
void Add(vector<Course>& cour) {} // 增
void Delete(vector<Course>& cour) {} // 删
void Modify(vector<Course>& cour) {} // 改
void Lookup(vector<Course>& cour) {} // 查
void Show(vector<Course>& cour) {} // 展示所有信息
private:
string _id; // 编号
string _name; // 课程名
bool _type; // 课程类型，1必修，0选修
int _hour; // 学时
int _credir; // 学分
int _count; // 选课人数
};
1.这个课程类的成员变量中记录了课程的基本信息，其中编号和课程名，这种有字符串属性的数据，我使用了string来存储。方便后续直接使用==或!=进行字符串的比较。
2.写了构造函数用来初始化数据。
3.将对课程的操作都写成成员函数，封装起来。后续的操作函数使用涉及到匿名对象，不了解的同学可以看下我之前的博客，这里就不再过多赘述了。
4.设计了一些接口，以便可以在类外访问私有成员变量。其中只有选课人数的接口是没有const修饰的，因为要在类外对其进行修改。
5.声明了输入输出流的重载，用来简化代码。学生类的输出流重载也要在课程类中友元声明一下，因为后续要在这个重载函数中访问课程的一些私有变量，且在这个重载函数中接口会失效。
学生类：
class Student
{
// 输入输出流重载
friend ostream& operator<<(ostream& out, const Student& s);
friend fstream& operator<<(fstream& fout, const Student& s);
// friend istream& operator>>(istream& in, Student& s); 这个重载不好实现，因为要查重
friend fstream& operator>>(fstream& fin, Student& s);
public:
Student()
: _id("None") // 学号
, _class("None") // 班级
, _name("None") // 姓名
, _num_compulsory(0)
, _num_elective(0)
{}
void Write(vector<Student>& stu, int n) {}
int Read(vector<Student>& stu) {}
void Add(vector<Student>& stu) {}
void Delete(vector<Student>& stu) {}
void Modify(vector<Student>& stu) {}
void Lookup(vector<Student>& stu) {}
void Show(vector<Student>& stu) {}
void Select(vector<Course>& cour, vector<Student>& stu) {} // 选课
void Deselect(vector<Course>& cour, vector<Student>& stu) {} // 退选
private:
string _id; // 学号
string _class; // 班级
string _name; // 名字
Course _cour_compulsory[SIZE_COMP]; // 必修课信息
Course _cour_elective[SIZE_ELECT]; // 选修课信息
int _num_compulsory; // 已选必修课数量
int _num_elective; // 已选选修课数量
};
1.学生类的成员变量记录了学生的基本信息。其中，课程的信息我用两个数组存了起来，SIZE_COMP和SIZE_ELECT是两个宏，分别对应学生所能选择的必修课和选修课最大数量。
2.学生相关的操作函数作为成员函数，写在Studnet类中，相比课程类多了选课和退选的模块。
3.写了构造函数来初始化数据。
4.声明了输入输出流重载，简化代码。
2.输入输出流重载的实现
课程类的输入输出重载：
ostream& operator<<(ostream& out, const Course& c)
{
out << c._id << "\t" << c._name << "\t" << (c._type ? "必修" : "选修") << "\t"
<< c._hour << "\t" << c._credir << "\t" << c._count;
return out;
}
fstream& operator<<(fstream& fout, const Course& c)
{
fout << c._id << "\t" << c._name << "\t" << c._type << "\t"
<< c._hour << "\t" << c._credir << "\t" << c._count;
return fout;
}
fstream& operator>>(fstream& fin, Course& c)
{
fin >> c._id >> c._name >> c._type
>> c._hour >> c._credir >> c._count;
return fin;
}
要写一个io流的输出重载，还要写一个文件流的输入输出重载。由于课程类在输入信息时还需要判断课程的编号是否重复，输入流重载略显复杂，还不如直接输入，所以这里就不再实现了。
学生类的输入输出重载：
ostream& operator<<(ostream& out, const Student& s)
{
out << s._id << "\t" << s._class << "\t" << s._name << "\t";
for (int i = 0; i < SIZE_COMP; i++)
out << s._cour_compulsory[i]._name << " ";
out << "\t";
for (int i = 0; i < SIZE_ELECT; i++)
out << s._cour_elective[i]._name << " ";
return out;
}
fstream& operator<<(fstream& fout, const Student& s)
{
fout << s._id << "\t" << s._class << "\t" << s._name << "\t";
for (int i = 0; i < SIZE_COMP; i++)
fout << s._cour_compulsory[i] << "\t";
for (int i = 0; i < SIZE_ELECT; i++)
fout << s._cour_elective[i] << "\t";
fout << s._num_compulsory << "\t" << s._num_elective;
return fout;
}
fstream& operator>>(fstream& fin, Student& s)
{
fin >> s._id >> s._class >> s._name;
for (int i = 0; i < SIZE_COMP; i++)
fin >> s._cour_compulsory[i];
for (int i = 0; i < SIZE_ELECT; i++)
fin >> s._cour_elective[i];
fin >> s._num_compulsory >> s._num_elective;
return fin;
}
学生类的io流输入和课程类同理，要判断学号是否重复，所以这里不再实现重载。应注意，学生类的io流输出重载中，课程信息只输出课程名；学生类的文件流输入输出重载中，复用了课程类的文件输入输出重载。
3.增删改查的实现
实现增删查改，需要借助两个全局的动态数组。vector<Course> cour和vector<Student> stu。
课程类：
class Course
{
friend ostream& operator<<(ostream& out, const Course& c);
friend fstream& operator<<(fstream& fout, const Course& c);
// friend istream& operator>>(istream& in, Course& c); 这个重载不好实现，因为要查重
friend fstream& operator>>(fstream& fin, Course& c);
friend ostream& operator<<(ostream& out, const Student& s);
public:
Course()
: _id("None")
, _name("None")
, _type(0)
, _hour(0)
, _credir(0)
, _count(0)
{}
const string c_id() { return _id; } // 编号的接口
const string c_name() { return _name; } // 名字的接口
int& c_count() { return _count; } // 选课人数的接口
const bool c_type() { return _type; } // 类型接口
void Write(vector<Course>& cour, int n)
{
fstream myfile;
myfile.open("course.txt", ios::out | ios::binary);
if (!myfile)
{
cout << "course.txt can't open." << endl;
abort();
}
myfile << n << endl << endl;
for (int i = 0; i < n; i++)
myfile << cour[i] << endl;
myfile.close();
}
int Read(vector<Course>& cour)
{
cour.clear();
fstream myfile;
myfile.open("course.txt", ios::in | ios::binary);
if (!myfile)
{
cout << "course.txt can't open." << endl;
abort();
}
int n;
myfile.seekg(0);
myfile >> n;
Course temp;
for (int i = 0; i < n; i++)
{
myfile >> temp;
cour.push_back(temp);
}
myfile.close();
return n;
}
void Add(vector<Course>& cour)
{
system("cls");
int n = Read(cour);
char sign = '0';
Course temp;
cout << "============ 增加课程信息 ============" << endl;
while (sign != 'n' && sign != 'N')
{
loop:
cout << "ID: ";
cin >> temp._id;
// 查重
int c = 0;
while (c < n)
{
c++;
if (temp._id == cour[n - c]._id)
{
cout << "编号重复，请重新输入。" << endl;
goto loop;
}
}
cout << "课程名: ";
cin >> temp._name;
cout << "课程类型(1必修，0选修): ";
cin >> temp._type;
cout << "学时: ";
cin >> temp._hour;
cout << "学分: ";
cin >> temp._credir;
n++;
cour.push_back(temp);
cout << "是否继续添加(y 或 n)";
cin >> sign;
}
// 保存进文件
Write(cour, n);
}
void Delete(vector<Course>& cour)
{
system("cls");
int n = Read(cour);
int i = 0;
string id;
cout << "============ 删除课程 ============" << endl;
cout << "请输入需要删除课程的编号: ";
cin >> id;
// 检查有没有这个课程
while (i < n && id != cour[i]._id)
i++;
if (i == n)
{
cout << "没找到该课程。" << endl;
system("pause");
return;
}
else
{
if (cour[i]._count)
{
cout << "所选人数不为零，请联系所有学生退选后，再删除该课程。" << endl;
system("pause");
return;
}
}
for (int j = i; j < n - 1; j++)
cour[j] = cour[j + 1]; // 编译器自动生成的赋值运算符重载
// 保存
char sign;
cout << "是否保存(y 或 n): ";
cin >> sign;
if (sign != 'n' && sign != 'N')
{
cour.erase(cour.end() - 1);
Write(cour, n - 1);
cout << "============ 删除成功 ============" << endl;
system("pause");
}
}
void Modify(vector<Course>& cour)
{
system("cls");
int n = Read(cour);
string id;
int i = 0;
cout << "============ 修改课程信息 ============" << endl;
cout << "请输入你想修改的课程id: ";
cin >> id;
// 看有没有这个课程
cin >> id;
while (i < n && id != cour[i]._id)
i++;
if (i == n)
{
cout << "没有找到该课程。" << endl;
system("pause");
return;
}
else
{
if (cour[i]._count)
{
cout << "所选人数不为零，请联系所有学生退选后，再修改课程信息。" << endl;
system("pause");
return;
}
}
cout << "-------------------------------------------------" << endl;
cout << "编号" << "\t" << "课程名" << "\t" << "类型" << "\t"
<< "学时" << "\t" << "学分" << "\t" << "选课人数" << endl;
cout << cour[i] << endl;
cout << "-------------------------------------------------" << endl;
cout << "请重新输入课程信息。" << endl;
cout << "课程名: ";
cin >> cour[i]._name;
cout << "课程类型(1必修，0选修): ";
cin >> cour[i]._type;
cout << "学时: ";
cin >> cour[i]._hour;
cout << "学分: ";
cin >> cour[i]._credir;
// 保存
char sign;
cout << "是否保存修改(y 或 n): ";
cin >> sign;
if (sign != 'n' && sign != 'N')
{
Write(cour, n);
cout << "============ 修改成功 ============" << endl;
system("pause");
}
}
void Lookup(vector<Course>& cour)
{
system("cls");
int n = Read(cour);
int i = 0;
string id;
cout << "============ 查找课程 ============" << endl;
cout << "请输入要查找课程的编号: ";
cin >> id;
// 检查是否存在
while (i < n && id != cour[i]._id)
i++;
if (i == n)
{
cout << "没有找到该课程。" << endl;
}
else
{
cout << "-------------------------------------------------" << endl;
cout << "编号" << "\t" << "课程名" << "\t" << "类型" << "\t"
<< "学时" << "\t" << "学分" << "\t" << "选课人数" << endl;
cout << "-------------------------------------------------" << endl;
cout << cour[i] << endl;
}
system("pause");
}
void Show(vector<Course>& cour)
{
system("cls");
int n = Read(cour);
cout << "============ 展示所有课程信息 ============" << endl;
cout << "-------------------------------------------------" << endl;
cout << "编号" << "\t" << "课程名" << "\t" << "类型" << "\t"
<< "学时" << "\t" << "学分" << "\t" << "选课人数" << endl;
cout << "-------------------------------------------------" << endl;
for (int i = 0; i < n; i++)
cout << cour[i] << endl;
system("pause");
}
private:
string _id; // 编号
string _name; // 课程名
bool _type; // 课程类型，1必修，0选修
int _hour; // 学时
int _credir; // 学分
int _count; // 选课人数
};
学生类：
class Student
{
friend ostream& operator<<(ostream& out, const Student& s);
friend fstream& operator<<(fstream& fout, const Student& s);
// friend istream& operator>>(istream& in, Student& s); 这个重载不好实现，因为要查重
friend fstream& operator>>(fstream& fin, Student& s);
public:
Student()
: _id("None") // 学号
, _class("None") // 班级
, _name("None") // 姓名
, _num_compulsory(0)
, _num_elective(0)
{}
void Write(vector<Student>& stu, int n)
{
fstream myfile;
myfile.open("student.txt", ios::out | ios::binary);
if (!myfile)
{
cout << "student.txt can't open." << endl;
abort();
}
myfile << n << endl << endl;
for (int i = 0; i < n; i++)
myfile << stu[i] << endl;
myfile.close();
}
int Read(vector<Student>& stu)
{
stu.clear();
fstream myfile;
myfile.open("student.txt", ios::in | ios::binary);
if (!myfile)
{
cout << "student.txt can't open." << endl;
abort();
}
int n;
myfile.seekg(0);
myfile >> n;
Student temp;
for (int i = 0; i < n; i++)
{
myfile >> temp;
stu.push_back(temp);
}
myfile.close();
return n;
}
void Add(vector<Student>& stu)
{
system("cls");
int n = Read(stu);
char sign = '0';
Student temp;
cout << "============ 添加学生 ============" << endl;
while (sign != 'n' && sign != 'N')
{
loop:
cout << "学号: ";
cin >> temp._id;
// 检查重复
int c = 0;
while (c < n)
{
c++;
if (temp._id == stu[n - c]._id)
{
cout << "学号重复，请重新输入。" << endl;
goto loop;
}
}
cout << "班级: ";
cin >> temp._class;
cout << "姓名: ";
cin >> temp._name;
n++;
stu.push_back(temp);
cout << "是否继续添加(y 或 n): ";
cin >> sign;
}
Write(stu, n);
}
void Delete(vector<Student>& stu)
{
system("cls");
int n = Read(stu);
int m = Course().Read(cour); // 课程数量
int i = 0;
string id;
cout << "============ 删除学生 =============" << endl;
cout << "请输入要删除学生的学号: ";
cin >> id;
while (i < n && id != stu[i]._id)
i++;
if (i == n)
{
cout << "没有找到该学生。" << endl;
system("pause");
return;
}
// 找到该学生所选的全部课程，并让这些课程的选课人数-1
if (stu[i]._num_compulsory)
{
while (stu[i]._num_compulsory > 0)
{
stu[i]._num_compulsory--;
int c = 0;
while (c < m)
{
if (stu[i]._cour_compulsory[stu[i]._num_compulsory].c_id() == cour[c].c_id())
{
cour[c].c_count()--;
break;
}
c++;
}
}
}
else if (stu[i]._num_elective)
{
while (stu[i]._num_elective > 0)
{
stu[i]._num_elective--;
int c = 0;
while (c < m)
{
if (stu[i]._cour_elective[stu[i]._num_elective].c_id() == cour[c].c_id())
{
cour[c].c_count()--;
break;
}
c++;
}
}
}
for (int j = i; j < n - 1; j++)
stu[j] = stu[j + 1];
// 保存
char sign;
cout << "请确定是否删除(y 或 n): ";
cin >> sign;
if (sign != 'n' && sign != 'N')
{
stu.erase(stu.end() - 1);
Write(stu, n - 1);
Course().Write(cour, m);
cout << "============ 删除成功 ============" << endl;
system("pause");
}
}
void Modify(vector<Student>& stu)
{
system("cls");
int n = Read(stu);
string id;
int i = 0;
cout << "============ 修改学生信息 ===========" << endl;
cout << "请输入你想修改学生的学号: ";
cin >> id;
while (i < n && id != stu[i]._id)
i++;
if (i == n)
{
cout << "找不到该学生。" << endl;
system("pause");
return;
}
cout << "-------------------------------------------------------" << endl;
cout << "学号: " << stu[i]._id << endl;
cout << "班级: " << stu[i]._class << endl;
cout << "姓名: " << stu[i]._name << endl;
cout << "-------------------------------------------------------" << endl;
cout << "请重新输入学生信息。" << endl;
cout << "班级: ";
cin >> stu[i]._class;
cout << "姓名: ";
cin >> stu[i]._name;
// 保存
char sign;
cout << "是否保存修改(y 或 n): ";
cin >> sign;
if (sign != 'n' && sign != 'N')
{
cout << "修改成功。" << endl;
Write(stu, n);
system("pause");
}
}
void Lookup(vector<Student>& stu)
{
system("cls");
int n = Read(stu);
Course().Read(cour);
int i = 0;
string id;
cout << "============== 查找学生 ==============" << endl;
cout << "请输入要查找学生的学号: ";
cin >> id;
while (i < n && id != stu[i]._id)
i++;
if (i == n)
{
cout << "找不到该学生。" << endl;
}
else
{
cout << stu[i] << endl;
}
system("pause");
}
void Show(vector<Student>& stu)
{
system("cls");
int n = Read(stu);
cout << "=============================== 展示所有学生信息 ==============================" << endl;
cout << "学号" << "\t" << "班级" << "\t" << "姓名" << "\t" << "必修课" << "\t" << "选修课" << endl;
cout << "-------------------------------------------------------------------------------" << endl;
for (int i = 0; i < n; i++)
cout << stu[i] << endl;
system("pause");
}
private:
string _id; // 学号
string _class; // 班级
string _name; // 名字
Course _cour_compulsory[SIZE_COMP]; // 必修课信息
Course _cour_elective[SIZE_ELECT]; // 选修课信息
int _num_compulsory; // 已选必修课数量
int _num_elective; // 已选选修课数量
};
可以发现，在查找和展示所有的函数中，我使用了输出流重载，让代码的可读性更高，也减少了代码量。
需要注意，和老版本不同，我没有再定义初始化文件的函数Input。所以这需要我们提前创建好两个文本文件，并进行相应的数据录入，具体格式如下：
-
course.txt:
-
student.txt:
4.多级菜单的实现
int choose_user()
{
loop:
system("cls");
int c = 0;
cout << "=================================================================" << endl;
cout << "-------------- 欢迎来到学生选课系统 ---------------" << endl;
cout << "请选择你的身份(1管理员 或 2学生)(输入0退出): ";
cin >> c;
string passwd;
if (c == 1)
{
cout << "请输入密码: ";
cin >> passwd;
if (passwd == string(PASSWORD)) // PASSWORD是一个宏，#define PASSWORD 密码
{
flag = 1;
cout << "登入成功." << endl;
system("pause");
}
else
{
cout << "密码错误." << endl;
system("pause");
goto loop;
}
}
else
flag = 0;
if (c < 0 || c > 2)
{
cout << "请输入 0-2." << endl;
system("pause");
goto loop;
}
return c;
}
void menu_course()
{
int c = 0;
while (1)
{
system("cls");
cout << "============ 课程菜单 ============" << endl;
cout << " 1. 增加课程 " << endl;
cout << " 2. 删除课程 " << endl;
cout << " 3. 修改课程 " << endl;
cout << " 4. 查找课程 " << endl;
cout << " 5. 展示所有课程 " << endl;
cout << " 0. 返回上级目录 " << endl;
cout << "----------------------------------" << endl;
cout << "请选择你的操作(0-6): ";
cin >> c;
switch (c)
{
case 1:
if (flag)
Course().Add(cour);
else
{
cout << "request denied." << endl;
system("pause");
}
break;
case 2:
if (flag)
Course().Delete(cour);
else
{
cout << "request denied." << endl;
system("pause");
}
break;
case 3:
if (flag)
Course().Modify(cour);
else
{
cout << "request denied." << endl;
system("pause");
}
break;
case 4:
Course().Lookup(cour);
break;
case 5:
Course().Show(cour);
break;
case 0:
cout << "------------ 返回成功 ------------" << endl;
system("pause");
return;
default:
cout << "请输入 0-6." << endl;
system("pause");
break;
}
}
}
void menu_student()
{
int c = 0;
while (1)
{
system("cls");
cout << "============ 学生菜单 ============" << endl;
cout << " 1. 添加学生 " << endl;
cout << " 2. 删除学生 " << endl;
cout << " 3. 修改学生 " << endl;
cout << " 4. 查找学生 " << endl;
cout << " 5. 展示所有学生信息 " << endl;
cout << " 6. 选课 " << endl;
cout << " 7. 退选 " << endl;
cout << " 0. 返回 " << endl;
cout << "----------------------------------" << endl;
cout << "请选择你的操作(0-7): ";
cin >> c;
switch (c)
{
case 1:
if (flag)
Student().Add(stu);
else
{
cout << "request denied." << endl;
system("pause");
}
break;
case 2:
if (flag)
Student().Delete(stu);
else
{
cout << "request denied." << endl;
system("pause");
}
break;
case 3:
if (flag)
Student().Modify(stu);
else
{
cout << "request denied." << endl;
system("pause");
}
break;
case 4:
Student().Lookup(stu);
break;
case 5:
Student().Show(stu);
break;
case 6:
Student().Select(cour, stu);
break;
case 7:
Student().Deselect(cour, stu);
break;
case 0:
cout << "------------ 返回成功 ------------" << endl;
system("pause");
return;
default:
cout << "请输入 0-7." << endl;
system("pause");
break;
}
}
}
int menu_main()
{
int c = 0;
while (1)
{
system("cls");
cout << "==========================================" << endl;
cout << " 1. 课程菜单 " << endl;
cout << " 2. 学生菜单 " << endl;
cout << " 0. 回到上级目录 " << endl;
cout << "请选择你的操作(0-2): ";
cin >> c;
if (c < 0 || c > 2)
{
cout << "请输入 0-2." << endl;
system("pause");
}
else
break;
}
return c;
}
int main()
{
cour.reserve(100);
stu.reserve(100);
while (1)
{
loop:
if (!choose_user())
{
cout << "=============== 谢谢使用！再见！ ===============" << endl;
return 0;
}
while (1)
{
switch (menu_main())
{
case 1:
menu_course();
break;
case 2:
menu_student();
break;
case 0:
cout << "=============== 返回成功 ===============" << endl;
system("pause");
goto loop;
default:
cout << "请输入 0-2." << endl;
system("pause");
break;
}
}
}
return 0;
}
这个菜单的实现基本和上一个版本相同，只不过密码处做了些许改动。定义了一个宏PASSWORD，方便后续的维护。
5.选课和退选的实现
class Student
{
public:
// ...
// 选课
void Select(vector<Course>& cour, vector<Student>& stu)
{
system("cls");
int n_cour = Course().Read(cour);
int n_stu = Read(stu);
int i = 0; // 学生
int j = 0; // 课程
string id_c; // 课程
string id_s; // 学生
cout << "============ 开始选课 ============" << endl;
cout << "请输入学生学号: ";
cin >> id_s;
while (i < n_stu && stu[i]._id != id_s)
i++;
if (i == n_stu)
{
cout << "找不到该学生。" << endl;
system("pause");
return;
}
cout << ("请输入想选择的课程编号: ");
cin >> id_c;
while (j < n_cour && cour[j].c_id() != id_c)
j++;
if (j == n_cour)
{
cout << "找不到该课程" << endl;
system("pause");
return;
}
if (cour[j].c_count() >= 60)
{
cout << "课程人数已达上限，选课失败。" << endl;
system("pause");
}
else
{
if (cour[j].c_type())
if (stu[i]._num_compulsory < 2)
{
int c = 0;
while (c < stu[i]._num_compulsory && cour[j].c_id() != stu[i]._cour_compulsory[c].c_id())
c++;
if (c < stu[i]._num_compulsory)
{
cout << "请勿重复选择课程。" << endl;
system("pause");
return;
}
stu[i]._cour_compulsory[stu[i]._num_compulsory] = cour[j];
stu[i]._num_compulsory++;
cour[j].c_count()++;
Course().Write(cour, n_cour);
Write(stu, n_stu);
cout << "选课成功。" << endl;
system("pause");
}
else
{
cout << "必修课数量已达上限，选课失败。" << endl;
system("pause");
}
else
{
if (stu[i]._num_elective < 1)
{
int c = 0;
while (c < stu[i]._num_elective && cour[j].c_id() != stu[i]._cour_elective[c].c_id())
c++;
if (c < stu[i]._num_elective)
{
cout << "请勿重复选择课程。" << endl;
system("pause");
return;
}
stu[i]._cour_elective[stu[i]._num_elective] = cour[j];
stu[i]._num_elective++;
cour[j].c_count()++;
Course().Write(cour, n_cour);
Write(stu, n_stu);
cout << "选课成功。" << endl;
system("pause");
}
else
{
cout << "选修课数量已达上限，选课失败。" << endl;
system("pause");
}
}
}
}
// 退选
void Deselect(vector<Course>& cour, vector<Student>& stu)
{
system("cls");
int n_cour = Course().Read(cour);
int n_stu = Read(stu);
int i = 0; // 学生
int j = 0; // 课程
string id_c; // 课程
string id_s; // 学生
cout << "============ 退选 ============" << endl;
cout << "请输入学生学号: ";
cin >> id_s;
while (i < n_stu && stu[i]._id != id_s)
i++;
if (i == n_stu)
{
cout << "找不到该学生。" << endl;
system("pause");
return;
}
cout << ("请输入想要退选的课程编号: ");
cin >> id_c;
while (j < n_cour && cour[j].c_id() != id_c)
j++;
if (j == n_cour)
{
cout << "找不到该课程" << endl;
system("pause");
return;
}
if (stu[i]._num_compulsory)
{
int c = stu[i]._num_compulsory - 1;
while (c >= 0)
{
if (stu[i]._cour_compulsory[c].c_id() == id_c)
{
cour[j].c_count()--;
stu[i]._num_compulsory--;
stu[i]._cour_compulsory[c] = Course();
// 重新排序
for (; c < stu[i]._num_compulsory; c++)
swap(stu[i]._cour_compulsory[c], stu[i]._cour_compulsory[c + 1]);
Write(stu, n_stu);
Course().Write(cour, n_cour);
cout << "退选成功。" << endl;
system("pause");
return;
}
c--;
}
if (stu[i]._cour_elective)
{
int c = stu[i]._num_elective - 1;
while (c >= 0)
{
if (stu[i]._cour_elective[c].c_id() == id_c)
{
cour[j].c_count()--;
stu[i]._num_elective--;
stu[i]._cour_elective[c] = Course();
for (; c < stu[i]._num_elective; c++)
swap(stu[i]._cour_elective[c], stu[i]._cour_elective[c + 1]);
Write(stu, n_stu);
Course().Write(cour, n_cour);
cout << "退选成功。" << endl;
system("pause");
return;
}
c--;
}
cout << "你并未选择该课程。" << endl;
system("pause");
return;
}
}
if (stu[i]._cour_elective)
{
int c = stu[i]._num_elective - 1;
while (c >= 0)
{
if (stu[i]._cour_elective[c].c_id() == id_c)
{
cour[j].c_count()--;
stu[i]._num_elective--;
stu[i]._cour_elective[c] = Course();
for (; c < stu[i]._num_elective; c++)
swap(stu[i]._cour_elective[c], stu[i]._cour_elective[c + 1]);
Write(stu, n_stu);
Course().Write(cour, n_cour);
cout << "退选成功。" << endl;
system("pause");
return;
}
c--;
}
cout << "你并未选择该课程。" << endl;
system("pause");
return;
}
}
private:
string _id; // 学号
string _class; // 班级
string _name; // 名字
Course _cour_compulsory[SIZE_COMP]; // 必修课信息
Course _cour_elective[SIZE_ELECT]; // 选修课信息
int _num_compulsory; // 已选必修课数量
int _num_elective; // 已选选修课数量
};
这一块的实现也和老版本没有多大区别，这里不再过多赘述，细节在我的上一篇博客中都有很详细的讲解。
5.完整代码
#define _CRT_SECURE_NO_WARNINGS
#include<iostream>
#include<fstream>
#include<string>
#include<vector>
using namespace std;
#define SIZE_COMP 2 // 可以选择的必修课数量
#define SIZE_ELECT 1 // 可选择的选修课数量
#define PASSWORD "123456" // 管理员密码
int flag = 0; // 确定身份状态的状态变量，0是学生，1是管理员，默认是0
class Student; // 向前声明学生类
class Course
{
friend ostream& operator<<(ostream& out, const Course& c);
friend fstream& operator<<(fstream& fout, const Course& c);
// friend istream& operator>>(istream& in, Course& c); 这个重载不好实现，因为要查重
friend fstream& operator>>(fstream& fin, Course& c);
friend ostream& operator<<(ostream& out, const Student& s);
public:
Course()
: _id("None")
, _name("None")
, _type(0)
, _hour(0)
, _credir(0)
, _count(0)
{}
const string c_id() { return _id; } // 编号的接口
const string c_name() { return _name; } // 名字的接口
int& c_count() { return _count; } // 选课人数的接口
const bool c_type() { return _type; } // 类型接口
void Write(vector<Course>& cour, int n)
{
fstream myfile;
myfile.open("course.txt", ios::out | ios::binary);
if (!myfile)
{
cout << "course.txt can't open." << endl;
abort();
}
myfile << n << endl << endl;
for (int i = 0; i < n; i++)
myfile << cour[i] << endl;
myfile.close();
}
int Read(vector<Course>& cour)
{
cour.clear();
fstream myfile;
myfile.open("course.txt", ios::in | ios::binary);
if (!myfile)
{
cout << "course.txt can't open." << endl;
abort();
}
int n;
myfile.seekg(0);
myfile >> n;
Course temp;
for (int i = 0; i < n; i++)
{
myfile >> temp;
cour.push_back(temp);
}
myfile.close();
return n;
}
void Add(vector<Course>& cour)
{
system("cls");
int n = Read(cour);
char sign = '0';
Course temp;
cout << "============ 增加课程信息 ============" << endl;
while (sign != 'n' && sign != 'N')
{
loop:
cout << "ID: ";
cin >> temp._id;
// 查重
int c = 0;
while (c < n)
{
c++;
if (temp._id == cour[n - c]._id)
{
cout << "编号重复，请重新输入。" << endl;
goto loop;
}
}
cout << "课程名: ";
cin >> temp._name;
cout << "课程类型(1必修，0选修): ";
cin >> temp._type;
cout << "学时: ";
cin >> temp._hour;
cout << "学分: ";
cin >> temp._credir;
n++;
cour.push_back(temp);
cout << "是否继续添加(y 或 n)";
cin >> sign;
}
// 保存进文件
Write(cour, n);
}
void Delete(vector<Course>& cour)
{
system("cls");
int n = Read(cour);
int i = 0;
string id;
cout << "============ 删除课程 ============" << endl;
cout << "请输入需要删除课程的编号: ";
cin >> id;
// 检查有没有这个课程
while (i < n && id != cour[i]._id)
i++;
if (i == n)
{
cout << "没找到该课程。" << endl;
system("pause");
return;
}
else
{
if (cour[i]._count)
{
cout << "所选人数不为零，请联系所有学生退选后，再删除该课程。" << endl;
system("pause");
return;
}
}
for (int j = i; j < n - 1; j++)
cour[j] = cour[j + 1]; // 编译器自动生成的赋值运算符重载
// 保存
char sign;
cout << "是否保存(y 或 n): ";
cin >> sign;
if (sign != 'n' && sign != 'N')
{
cour.erase(cour.end() - 1);
Write(cour, n - 1);
cout << "============ 删除成功 ============" << endl;
system("pause");
}
}
void Modify(vector<Course>& cour)
{
system("cls");
int n = Read(cour);
string id;
int i = 0;
cout << "============ 修改课程信息 ============" << endl;
cout << "请输入你想修改的课程id: ";
cin >> id;
// 看有没有这个课程
cin >> id;
while (i < n && id != cour[i]._id)
i++;
if (i == n)
{
cout << "没有找到该课程。" << endl;
system("pause");
return;
}
else
{
if (cour[i]._count)
{
cout << "所选人数不为零，请联系所有学生退选后，再修改课程信息。" << endl;
system("pause");
return;
}
}
cout << "-------------------------------------------------" << endl;
cout << "编号" << "\t" << "课程名" << "\t" << "类型" << "\t"
<< "学时" << "\t" << "学分" << "\t" << "选课人数" << endl;
cout << cour[i] << endl;
cout << "-------------------------------------------------" << endl;
cout << "请重新输入课程信息。" << endl;
cout << "课程名: ";
cin >> cour[i]._name;
cout << "课程类型(1必修，0选修): ";
cin >> cour[i]._type;
cout << "学时: ";
cin >> cour[i]._hour;
cout << "学分: ";
cin >> cour[i]._credir;
// 保存
char sign;
cout << "是否保存修改(y 或 n): ";
cin >> sign;
if (sign != 'n' && sign != 'N')
{
Write(cour, n);
cout << "============ 修改成功 ============" << endl;
system("pause");
}
}
void Lookup(vector<Course>& cour)
{
system("cls");
int n = Read(cour);
int i = 0;
string id;
cout << "============ 查找课程 ============" << endl;
cout << "请输入要查找课程的编号: ";
cin >> id;
// 检查是否存在
while (i < n && id != cour[i]._id)
i++;
if (i == n)
{
cout << "没有找到该课程。" << endl;
}
else
{
cout << "-------------------------------------------------" << endl;
cout << "编号" << "\t" << "课程名" << "\t" << "类型" << "\t"
<< "学时" << "\t" << "学分" << "\t" << "选课人数" << endl;
cout << "-------------------------------------------------" << endl;
cout << cour[i] << endl;
}
system("pause");
}
void Show(vector<Course>& cour)
{
system("cls");
int n = Read(cour);
cout << "============ 展示所有课程信息 ============" << endl;
cout << "-------------------------------------------------" << endl;
cout << "编号" << "\t" << "课程名" << "\t" << "类型" << "\t"
<< "学时" << "\t" << "学分" << "\t" << "选课人数" << endl;
cout << "-------------------------------------------------" << endl;
for (int i = 0; i < n; i++)
cout << cour[i] << endl;
system("pause");
}
private:
string _id; // 编号
string _name; // 课程名
bool _type; // 课程类型，1必修，0选修
int _hour; // 学时
int _credir; // 学分
int _count; // 选课人数
};
vector<Course> cour;
ostream& operator<<(ostream& out, const Course& c)
{
out << c._id << "\t" << c._name << "\t" << (c._type ? "必修" : "选修") << "\t"
<< c._hour << "\t" << c._credir << "\t" << c._count;
return out;
}
fstream& operator<<(fstream& fout, const Course& c)
{
fout << c._id << "\t" << c._name << "\t" << c._type << "\t"
<< c._hour << "\t" << c._credir << "\t" << c._count;
return fout;
}
fstream& operator>>(fstream& fin, Course& c)
{
fin >> c._id >> c._name >> c._type
>> c._hour >> c._credir >> c._count;
return fin;
}
class Student
{
friend ostream& operator<<(ostream& out, const Student& s);
friend fstream& operator<<(fstream& fout, const Student& s);
// friend istream& operator>>(istream& in, Student& s); 这个重载不好实现，因为要查重
friend fstream& operator>>(fstream& fin, Student& s);
public:
Student()
: _id("None") // 学号
, _class("None") // 班级
, _name("None") // 姓名
, _num_compulsory(0)
, _num_elective(0)
{}
void Write(vector<Student>& stu, int n)
{
fstream myfile;
myfile.open("student.txt", ios::out | ios::binary);
if (!myfile)
{
cout << "student.txt can't open." << endl;
abort();
}
myfile << n << endl << endl;
for (int i = 0; i < n; i++)
myfile << stu[i] << endl;
myfile.close();
}
int Read(vector<Student>& stu)
{
stu.clear();
fstream myfile;
myfile.open("student.txt", ios::in | ios::binary);
if (!myfile)
{
cout << "student.txt can't open." << endl;
abort();
}
int n;
myfile.seekg(0);
myfile >> n;
Student temp;
for (int i = 0; i < n; i++)
{
myfile >> temp;
stu.push_back(temp);
}
myfile.close();
return n;
}
void Add(vector<Student>& stu)
{
system("cls");
int n = Read(stu);
char sign = '0';
Student temp;
cout << "============ 添加学生 ============" << endl;
while (sign != 'n' && sign != 'N')
{
loop:
cout << "学号: ";
cin >> temp._id;
// 检查重复
int c = 0;
while (c < n)
{
c++;
if (temp._id == stu[n - c]._id)
{
cout << "学号重复，请重新输入。" << endl;
goto loop;
}
}
cout << "班级: ";
cin >> temp._class;
cout << "姓名: ";
cin >> temp._name;
n++;
stu.push_back(temp);
cout << "是否继续添加(y 或 n): ";
cin >> sign;
}
Write(stu, n);
}
void Delete(vector<Student>& stu)
{
system("cls");
int n = Read(stu);
int m = Course().Read(cour); // 课程数量
int i = 0;
string id;
cout << "============ 删除学生 =============" << endl;
cout << "请输入要删除学生的学号: ";
cin >> id;
while (i < n && id != stu[i]._id)
i++;
if (i == n)
{
cout << "没有找到该学生。" << endl;
system("pause");
return;
}
// 找到该学生所选的全部课程，并让这些课程的选课人数-1
if (stu[i]._num_compulsory)
{
while (stu[i]._num_compulsory > 0)
{
stu[i]._num_compulsory--;
int c = 0;
while (c < m)
{
if (stu[i]._cour_compulsory[stu[i]._num_compulsory].c_id() == cour[c].c_id())
{
cour[c].c_count()--;
break;
}
c++;
}
}
}
else if (stu[i]._num_elective)
{
while (stu[i]._num_elective > 0)
{
stu[i]._num_elective--;
int c = 0;
while (c < m)
{
if (stu[i]._cour_elective[stu[i]._num_elective].c_id() == cour[c].c_id())
{
cour[c].c_count()--;
break;
}
c++;
}
}
}
for (int j = i; j < n - 1; j++)
stu[j] = stu[j + 1];
// 保存
char sign;
cout << "请确定是否删除(y 或 n): ";
cin >> sign;
if (sign != 'n' && sign != 'N')
{
stu.erase(stu.end() - 1);
Write(stu, n - 1);
Course().Write(cour, m);
cout << "============ 删除成功 ============" << endl;
system("pause");
}
}
void Modify(vector<Student>& stu)
{
system("cls");
int n = Read(stu);
string id;
int i = 0;
cout << "============ 修改学生信息 ===========" << endl;
cout << "请输入你想修改学生的学号: ";
cin >> id;
while (i < n && id != stu[i]._id)
i++;
if (i == n)
{
cout << "找不到该学生。" << endl;
system("pause");
return;
}
cout << "-------------------------------------------------------" << endl;
cout << "学号: " << stu[i]._id << endl;
cout << "班级: " << stu[i]._class << endl;
cout << "姓名: " << stu[i]._name << endl;
cout << "-------------------------------------------------------" << endl;
cout << "请重新输入学生信息。" << endl;
cout << "班级: ";
cin >> stu[i]._class;
cout << "姓名: ";
cin >> stu[i]._name;
// 保存
char sign;
cout << "是否保存修改(y 或 n): ";
cin >> sign;
if (sign != 'n' && sign != 'N')
{
cout << "修改成功。" << endl;
Write(stu, n);
system("pause");
}
}
void Lookup(vector<Student>& stu)
{
system("cls");
int n = Read(stu);
Course().Read(cour);
int i = 0;
string id;
cout << "============== 查找学生 ==============" << endl;
cout << "请输入要查找学生的学号: ";
cin >> id;
while (i < n && id != stu[i]._id)
i++;
if (i == n)
{
cout << "找不到该学生。" << endl;
}
else
{
cout << stu[i] << endl;
}
system("pause");
}
void Show(vector<Student>& stu)
{
system("cls");
int n = Read(stu);
cout << "=============================== 展示所有学生信息 ==============================" << endl;
cout << "学号" << "\t" << "班级" << "\t" << "姓名" << "\t" << "必修课" << "\t" << "选修课" << endl;
cout << "-------------------------------------------------------------------------------" << endl;
for (int i = 0; i < n; i++)
cout << stu[i] << endl;
system("pause");
}
void Select(vector<Course>& cour, vector<Student>& stu)
{
system("cls");
int n_cour = Course().Read(cour);
int n_stu = Read(stu);
int i = 0; // 学生
int j = 0; // 课程
string id_c; // 课程
string id_s; // 学生
cout << "============ 开始选课 ============" << endl;
cout << "请输入学生学号: ";
cin >> id_s;
while (i < n_stu && stu[i]._id != id_s)
i++;
if (i == n_stu)
{
cout << "找不到该学生。" << endl;
system("pause");
return;
}
cout << ("请输入想选择的课程编号: ");
cin >> id_c;
while (j < n_cour && cour[j].c_id() != id_c)
j++;
if (j == n_cour)
{
cout << "找不到该课程" << endl;
system("pause");
return;
}
if (cour[j].c_count() >= 60)
{
cout << "课程人数已达上限，选课失败。" << endl;
system("pause");
}
else
{
if (cour[j].c_type())
if (stu[i]._num_compulsory < 2)
{
int c = 0;
while (c < stu[i]._num_compulsory && cour[j].c_id() != stu[i]._cour_compulsory[c].c_id())
c++;
if (c < stu[i]._num_compulsory)
{
cout << "请勿重复选择课程。" << endl;
system("pause");
return;
}
stu[i]._cour_compulsory[stu[i]._num_compulsory] = cour[j];
stu[i]._num_compulsory++;
cour[j].c_count()++;
Course().Write(cour, n_cour);
Write(stu, n_stu);
cout << "选课成功。" << endl;
system("pause");
}
else
{
cout << "必修课数量已达上限，选课失败。" << endl;
system("pause");
}
else
{
if (stu[i]._num_elective < 1)
{
int c = 0;
while (c < stu[i]._num_elective && cour[j].c_id() != stu[i]._cour_elective[c].c_id())
c++;
if (c < stu[i]._num_elective)
{
cout << "请勿重复选择课程。" << endl;
system("pause");
return;
}
stu[i]._cour_elective[stu[i]._num_elective] = cour[j];
stu[i]._num_elective++;
cour[j].c_count()++;
Course().Write(cour, n_cour);
Write(stu, n_stu);
cout << "选课成功。" << endl;
system("pause");
}
else
{
cout << "选修课数量已达上限，选课失败。" << endl;
system("pause");
}
}
}
}
void Deselect(vector<Course>& cour, vector<Student>& stu)
{
system("cls");
int n_cour = Course().Read(cour);
int n_stu = Read(stu);
int i = 0; // 学生
int j = 0; // 课程
string id_c; // 课程
string id_s; // 学生
cout << "============ 退选 ============" << endl;
cout << "请输入学生学号: ";
cin >> id_s;
while (i < n_stu && stu[i]._id != id_s)
i++;
if (i == n_stu)
{
cout << "找不到该学生。" << endl;
system("pause");
return;
}
cout << ("请输入想要退选的课程编号: ");
cin >> id_c;
while (j < n_cour && cour[j].c_id() != id_c)
j++;
if (j == n_cour)
{
cout << "找不到该课程" << endl;
system("pause");
return;
}
if (stu[i]._num_compulsory)
{
int c = stu[i]._num_compulsory - 1;
while (c >= 0)
{
if (stu[i]._cour_compulsory[c].c_id() == id_c)
{
cour[j].c_count()--;
stu[i]._num_compulsory--;
stu[i]._cour_compulsory[c] = Course();
// 重新排序
for (; c < stu[i]._num_compulsory; c++)
swap(stu[i]._cour_compulsory[c], stu[i]._cour_compulsory[c + 1]);
Write(stu, n_stu);
Course().Write(cour, n_cour);
cout << "退选成功。" << endl;
system("pause");
return;
}
c--;
}
if (stu[i]._cour_elective)
{
int c = stu[i]._num_elective - 1;
while (c >= 0)
{
if (stu[i]._cour_elective[c].c_id() == id_c)
{
cour[j].c_count()--;
stu[i]._num_elective--;
stu[i]._cour_elective[c] = Course();
for (; c < stu[i]._num_elective; c++)
swap(stu[i]._cour_elective[c], stu[i]._cour_elective[c + 1]);
Write(stu, n_stu);
Course().Write(cour, n_cour);
cout << "退选成功。" << endl;
system("pause");
return;
}
c--;
}
cout << "你并未选择该课程。" << endl;
system("pause");
return;
}
}
if (stu[i]._cour_elective)
{
int c = stu[i]._num_elective - 1;
while (c >= 0)
{
if (stu[i]._cour_elective[c].c_id() == id_c)
{
cour[j].c_count()--;
stu[i]._num_elective--;
stu[i]._cour_elective[c] = Course();
for (; c < stu[i]._num_elective; c++)
swap(stu[i]._cour_elective[c], stu[i]._cour_elective[c + 1]);
Write(stu, n_stu);
Course().Write(cour, n_cour);
cout << "退选成功。" << endl;
system("pause");
return;
}
c--;
}
cout << "你并未选择该课程。" << endl;
system("pause");
return;
}
}
private:
string _id; // 学号
string _class; // 班级
string _name; // 名字
Course _cour_compulsory[SIZE_COMP]; // 必修课信息
Course _cour_elective[SIZE_ELECT]; // 选修课信息
int _num_compulsory; // 已选必修课数量
int _num_elective; // 已选选修课数量
};
vector<Student> stu;
ostream& operator<<(ostream& out, const Student& s)
{
out << s._id << "\t" << s._class << "\t" << s._name << "\t";
for (int i = 0; i < SIZE_COMP; i++)
out << s._cour_compulsory[i]._name << " ";
out << "\t";
for (int i = 0; i < SIZE_ELECT; i++)
out << s._cour_elective[i]._name << " ";
return out;
}
fstream& operator<<(fstream& fout, const Student& s)
{
fout << s._id << "\t" << s._class << "\t" << s._name << "\t";
for (int i = 0; i < SIZE_COMP; i++)
fout << s._cour_compulsory[i] << "\t";
for (int i = 0; i < SIZE_ELECT; i++)
fout << s._cour_elective[i] << "\t";
fout << s._num_compulsory << "\t" << s._num_elective;
return fout;
}
fstream& operator>>(fstream& fin, Student& s)
{
fin >> s._id >> s._class >> s._name;
for (int i = 0; i < SIZE_COMP; i++)
fin >> s._cour_compulsory[i];
for (int i = 0; i < SIZE_ELECT; i++)
fin >> s._cour_elective[i];
fin >> s._num_compulsory >> s._num_elective;
return fin;
}
// --------------------------------------------------------------------------------------------------//
int choose_user()
{
loop:
system("cls");
int c = 0;
cout << "=================================================================" << endl;
cout << "-------------- 欢迎来到学生选课系统 ---------------" << endl;
cout << "请选择你的身份(1管理员 或 2学生)(输入0退出): ";
cin >> c;
string passwd;
if (c == 1)
{
cout << "请输入密码: ";
cin >> passwd;
if (passwd == string(PASSWORD))
{
flag = 1;
cout << "登入成功." << endl;
system("pause");
}
else
{
cout << "密码错误." << endl;
system("pause");
goto loop;
}
}
else
flag = 0;
if (c < 0 || c > 2)
{
cout << "请输入 0-2." << endl;
system("pause");
goto loop;
}
return c;
}
void menu_course()
{
int c = 0;
while (1)
{
system("cls");
cout << "============ 课程菜单 ============" << endl;
cout << " 1. 增加课程 " << endl;
cout << " 2. 删除课程 " << endl;
cout << " 3. 修改课程 " << endl;
cout << " 4. 查找课程 " << endl;
cout << " 5. 展示所有课程 " << endl;
cout << " 0. 返回上级目录 " << endl;
cout << "----------------------------------" << endl;
cout << "请选择你的操作(0-6): ";
cin >> c;
switch (c)
{
case 1:
if (flag)
Course().Add(cour);
else
{
cout << "request denied." << endl;
system("pause");
}
break;
case 2:
if (flag)
Course().Delete(cour);
else
{
cout << "request denied." << endl;
system("pause");
}
break;
case 3:
if (flag)
Course().Modify(cour);
else
{
cout << "request denied." << endl;
system("pause");
}
break;
case 4:
Course().Lookup(cour);
break;
case 5:
Course().Show(cour);
break;
case 0:
cout << "------------ 返回成功 ------------" << endl;
system("pause");
return;
default:
cout << "请输入 0-6." << endl;
system("pause");
break;
}
}
}
void menu_student()
{
int c = 0;
while (1)
{
system("cls");
cout << "============ 学生菜单 ============" << endl;
cout << " 1. 添加学生 " << endl;
cout << " 2. 删除学生 " << endl;
cout << " 3. 修改学生 " << endl;
cout << " 4. 查找学生 " << endl;
cout << " 5. 展示所有学生信息 " << endl;
cout << " 6. 选课 " << endl;
cout << " 7. 退选 " << endl;
cout << " 0. 返回 " << endl;
cout << "----------------------------------" << endl;
cout << "请选择你的操作(0-7): ";
cin >> c;
switch (c)
{
case 1:
if (flag)
Student().Add(stu);
else
{
cout << "request denied." << endl;
system("pause");
}
break;
case 2:
if (flag)
Student().Delete(stu);
else
{
cout << "request denied." << endl;
system("pause");
}
break;
case 3:
if (flag)
Student().Modify(stu);
else
{
cout << "request denied." << endl;
system("pause");
}
break;
case 4:
Student().Lookup(stu);
break;
case 5:
Student().Show(stu);
break;
case 6:
Student().Select(cour, stu);
break;
case 7:
Student().Deselect(cour, stu);
break;
case 0:
cout << "------------ 返回成功 ------------" << endl;
system("pause");
return;
default:
cout << "请输入 0-7." << endl;
system("pause");
break;
}
}
}
int menu_main()
{
int c = 0;
while (1)
{
system("cls");
cout << "==========================================" << endl;
cout << " 1. 课程菜单 " << endl;
cout << " 2. 学生菜单 " << endl;
cout << " 0. 回到上级目录 " << endl;
cout << "请选择你的操作(0-2): ";
cin >> c;
if (c < 0 || c > 2)
{
cout << "请输入 0-2." << endl;
system("pause");
}
else
break;
}
return c;
}
int main()
{
cour.reserve(100);
stu.reserve(100);
while (1)
{
loop:
if (!choose_user())
{
cout << "=============== 谢谢使用！再见！ ===============" << endl;
return 0;
}
while (1)
{
switch (menu_main())
{
case 1:
menu_course();
break;
case 2:
menu_student();
break;
case 0:
cout << "=============== 返回成功 ===============" << endl;
system("pause");
goto loop;
default:
cout << "请输入 0-2." << endl;
system("pause");
break;
}
}
}
return 0;
}
文章来源:https://blog.csdn.net/weixin_73870552/article/details/135351654
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本文来自互联网用户投稿，该文观点仅代表作者本人，不代表本站立场。本站仅提供信息存储空间服务，不拥有所有权，不承担相关法律责任。 如若内容造成侵权/违法违规/事实不符，请联系我的编程经验分享网邮箱：chenni525@qq.com进行投诉反馈，一经查实，立即删除！
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