C++完整的学生管理系统

实现功能

添加、删除、修改学生
为学生添加、删除、修改成绩
将数据保存在students.txt和grades.txt里

效果图（部分功能）

添加学生

添加成绩

源代码

这里就不分多个文件了编译时在连接器命令行加入以下命令 -std=c++11

#include <iostream>
#include <fstream>
#include <vector>
#include <string>
#include <algorithm>
#include <limits>using namespace std;struct Student {string id;string name;string gender;int age;string class_name;
};struct Grade {string student_id;string course_name;int grade;
};vector<Student> students;
vector<Grade> grades;void loadStudents() {ifstream infile("students.txt");if (infile.is_open()) {Student s;while (infile >> s.id >> s.name >> s.gender >> s.age >> s.class_name) {students.push_back(s);}infile.close();}
}void saveStudents() {ofstream outfile("students.txt");for (const auto& s : students) {outfile << s.id << " " << s.name << " " << s.gender << " " << s.age << " " << s.class_name << endl;}
}void loadGrades() {ifstream infile("grades.txt");if (infile.is_open()) {Grade g;while (infile >> g.student_id >> g.course_name >> g.grade) {grades.push_back(g);}infile.close();}
}void saveGrades() {ofstream outfile("grades.txt");for (const auto& g : grades) {outfile << g.student_id << " " << g.course_name << " " << g.grade << endl;}
}void addStudent() {Student s;cout << "输入学生学号 Enter student ID: ";cin >> s.id;cout << "输入学生姓名 Enter student name: ";cin >> s.name;cout << "输入学生性别 Enter student gender: ";cin >> s.gender;cout << "输入学生年龄 Enter student age: ";while (!(cin >> s.age)) {cin.clear();cin.ignore(numeric_limits<streamsize>::max(), '\n');cout << "无效输入，请输入有效的年龄 Invalid input, please enter a valid age: ";}cout << "输入学生班级 Enter student class: ";cin >> s.class_name;students.push_back(s);saveStudents();cout << "学生添加成功 Student added successfully." << endl;
}void modifyStudent() {string id;cout << "输入要修改的学生ID Enter student ID to modify: ";cin >> id;auto it = find_if(students.begin(), students.end(), [&id](const Student& s) {return s.id == id;});if (it != students.end()) {cout << "输入学生新的姓名 Enter new student name: ";cin >> it->name;cout << "输入学生新的性别 Enter new student gender: ";cin >> it->gender;cout << "输入学生新的年龄 Enter new student age: ";while (!(cin >> it->age)) {cin.clear();cin.ignore(numeric_limits<streamsize>::max(), '\n');cout << "无效输入，请输入有效的年龄 Invalid input, please enter a valid age: ";}cout << "输入学生新的班级 Enter new student class: ";cin >> it->class_name;saveStudents();cout << "学生信息修改成功 Student information modified successfully." << endl;} else {cout << "找不到学生ID Student ID not found." << endl;}
}void deleteStudent() {string id;cout << "输入要删除的学生ID Enter student ID to delete: ";cin >> id;auto it = remove_if(students.begin(), students.end(), [&id](const Student& s) {return s.id == id;});if (it != students.end()) {students.erase(it, students.end());saveStudents();cout << "学生已成功删除 Student deleted successfully." << endl;} else {cout << "找不到学生ID Student ID not found." << endl;}
}void queryStudent() {string id;cout << "输入要查询的学生ID Enter student ID to query: ";cin >> id;auto it = find_if(students.begin(), students.end(), [&id](const Student& s) {return s.id == id;});if (it != students.end()) {cout << "学生学号 Student ID: " << it->id << endl;cout << "学生姓名 Student name: " << it->name << endl;cout << "学生性别 Student gender: " << it->gender << endl;cout << "学生年龄 Student age: " << it->age << endl;cout << "学生班级 Student class: " << it->class_name << endl;} else {cout << "找不到学生ID Student ID not found." << endl;}
}void addGrade() {Grade g;cout << "输入学生学号 Enter student ID: ";cin >> g.student_id;cout << "输入课程名称 Enter course name: ";cin >> g.course_name;cout << "输入等级 Enter grade: ";while (!(cin >> g.grade)) {cin.clear();cin.ignore(numeric_limits<streamsize>::max(), '\n');cout << "无效输入，请输入有效的等级 Invalid input, please enter a valid grade: ";}grades.push_back(g);saveGrades();cout << "成绩添加成功 Grade added successfully." << endl;
}void modifyGrade() {string id, course;cout << "输入学生学号 Enter student ID: ";cin >> id;cout << "输入课程名称 Enter course name: ";cin >> course;auto it = find_if(grades.begin(), grades.end(), [&id, &course](const Grade& g) {return g.student_id == id && g.course_name == course;});if (it != grades.end()) {cout << "输入新的等级 Enter new grade: ";while (!(cin >> it->grade)) {cin.clear();cin.ignore(numeric_limits<streamsize>::max(), '\n');cout << "无效输入，请输入有效的等级 Invalid input, please enter a valid grade: ";}saveGrades();cout << "成绩修改成功 Grade modified successfully." << endl;} else {cout << "未找到成绩记录 Grade record not found." << endl;}
}void deleteGrade() {string id, course;cout << "输入学生学号 Enter student ID: ";cin >> id;cout << "输入课程名称 Enter course name: ";cin >> course;auto it = remove_if(grades.begin(), grades.end(), [&id, &course](const Grade& g) {return g.student_id == id && g.course_name == course;});if (it != grades.end()) {grades.erase(it, grades.end());saveGrades();cout << "成绩删除成功 Grade deleted successfully." << endl;} else {cout << "未找到成绩记录 Grade record not found." << endl;}
}void queryGrade() {string id, course;cout << "输入学生学号 Enter student ID: ";cin >> id;cout << "输入课程名称 Enter course name: ";cin >> course;auto it = find_if(grades.begin(), grades.end(), [&id, &course](const Grade& g) {return g.student_id == id && g.course_name == course;});if (it != grades.end()) {cout << "学生学号 Student ID: " << it->student_id << endl;cout << "课程名称 Course name: " << it->course_name << endl;cout << "成绩 Grade: " << it->grade << endl;} else {cout << "未找到成绩记录 Grade record not found." << endl;}
}void displayMenu() {cout << "学生管理系统 Student Management System" << endl;cout << "1.添加学生 Add Student" << endl;cout << "2.修改学生 Modify Student" << endl;cout << "3.删除学生 Delete Student" << endl;cout << "4.查找学生 Query Student" << endl;cout << "5.添加成绩 Add Grade" << endl;cout << "6.修改成绩 Modify Grade" << endl;cout << "7.删除成绩 Delete Grade" << endl;cout << "8.查找成绩 Query Grade" << endl;cout << "9.退出 Exit" << endl;
}enum MenuOption {ADD_STUDENT = 1,MODIFY_STUDENT,DELETE_STUDENT,QUERY_STUDENT,ADD_GRADE,MODIFY_GRADE,DELETE_GRADE,QUERY_GRADE,EXIT
};int main() {loadStudents();loadGrades();int choice;do {displayMenu();cout << "输入您的选择 Enter your choice: ";while (!(cin >> choice)) {cin.clear();cin.ignore(numeric_limits<streamsize>::max(), '\n');cout << "无效输入，请输入有效的选项 Invalid input, please enter a valid option: ";}MenuOption option = static_cast<MenuOption>(choice);switch (option) {case ADD_STUDENT:addStudent();break;case MODIFY_STUDENT:modifyStudent();break;case DELETE_STUDENT:deleteStudent();break;case QUERY_STUDENT:queryStudent();break;case ADD_GRADE:addGrade();break;case MODIFY_GRADE:modifyGrade();break;case DELETE_GRADE:deleteGrade();break;case QUERY_GRADE:queryGrade();break;case EXIT:cout << "退出 Exiting..." << endl;break;default:cout << "选择无效，请重试 Invalid choice. Please try again." << endl;}} while (choice != EXIT);return 0;
}