设计一个完整的C++程序

设计一个完整的C++程序需要明确目的、需求和设计思路。以下是一个设计和实现一个简单的学生信息管理系统的完整示例。该程序可以执行添加学生、显示所有学生、查找学生和退出程序等功能。

需求分析

1. 添加学生信息：包括学号、姓名和年龄。
2. 显示所有学生信息。
3. 根据学号查找学生信息。
4. 退出程序。

设计思路

1. 使用一个Student类来封装学生的信息。
2. 使用一个vector来存储多个学生信息。
3. 提供一个菜单驱动的用户界面，用户可以选择不同的操作。

实现步骤

步骤一：定义Student类

cpp
复制代码
#include <iostream>
#include <vector>
#include <string>

class Student {
private:
    int id;
    std::string name;
    int age;

public:
    Student(int id, std::string name, int age) : id(id), name(name), age(age) {}

    int getId() const {
        return id;
    }

    std::string getName() const {
        return name;
    }

    int getAge() const {
        return age;
    }

    void display() const {
        std::cout << "ID: " << id << ", Name: " << name << ", Age: " << age << std::endl;
    }
};

步骤二：定义管理学生信息的函数

cpp
复制代码
void addStudent(std::vector<Student>& students) {
    int id;
    std::string name;
    int age;

    std::cout << "Enter student ID: ";
    std::cin >> id;
    std::cout << "Enter student name: ";
    std::cin.ignore();  // 清除输入缓冲区
    std::getline(std::cin, name);
    std::cout << "Enter student age: ";
    std::cin >> age;

    Student newStudent(id, name, age);
    students.push_back(newStudent);
    std::cout << "Student added successfully!" << std::endl;
}

void displayAllStudents(const std::vector<Student>& students) {
    if (students.empty()) {
        std::cout << "No students found!" << std::endl;
    } else {
        for (const auto& student : students) {
            student.display();
        }
    }
}

void findStudentById(const std::vector<Student>& students, int id) {
    for (const auto& student : students) {
        if (student.getId() == id) {
            student.display();
            return;
        }
    }
    std::cout << "Student with ID " << id << " not found." << std::endl;
}

步骤三：实现主函数及菜单驱动界面

cpp
复制代码
int main() {
    std::vector<Student> students;
    int choice;

    while (true) {
        std::cout << "\nStudent Management System\n";
        std::cout << "1. Add Student\n";
        std::cout << "2. Display All Students\n";
        std::cout << "3. Find Student by ID\n";
        std::cout << "4. Exit\n";
        std::cout << "Enter your choice: ";
        std::cin >> choice;

        switch (choice) {
            case 1:
                addStudent(students);
                break;
            case 2:
                displayAllStudents(students);
                break;
            case 3: {
                int id;
                std::cout << "Enter student ID: ";
                std::cin >> id;
                findStudentById(students, id);
                break;
            }
            case 4:
                std::cout << "Exiting the program." << std::endl;
                return 0;
            default:
                std::cout << "Invalid choice. Please try again." << std::endl;
        }
    }
}

完整代码

cpp
复制代码
#include <iostream>
#include <vector>
#include <string>

class Student {
private:
    int id;
    std::string name;
    int age;

public:
    Student(int id, std::string name, int age) : id(id), name(name), age(age) {}

    int getId() const {
        return id;
    }

    std::string getName() const {
        return name;
    }

    int getAge() const {
        return age;
    }

    void display() const {
        std::cout << "ID: " << id << ", Name: " << name << ", Age: " << age << std::endl;
    }
};

void addStudent(std::vector<Student>& students) {
    int id;
    std::string name;
    int age;

    std::cout << "Enter student ID: ";
    std::cin >> id;
    std::cout << "Enter student name: ";
    std::cin.ignore();  // 清除输入缓冲区
    std::getline(std::cin, name);
    std::cout << "Enter student age: ";
    std::cin >> age;

    Student newStudent(id, name, age);
    students.push_back(newStudent);
    std::cout << "Student added successfully!" << std::endl;
}

void displayAllStudents(const std::vector<Student>& students) {
    if (students.empty()) {
        std::cout << "No students found!" << std::endl;
    } else {
        for (const auto& student : students) {
            student.display();
        }
    }
}

void findStudentById(const std::vector<Student>& students, int id) {
    for (const auto& student : students) {
        if (student.getId() == id) {
            student.display();
            return;
        }
    }
    std::cout << "Student with ID " << id << " not found." << std::endl;
}

int main() {
    std::vector<Student> students;
    int choice;

    while (true) {
        std::cout << "\nStudent Management System\n";
        std::cout << "1. Add Student\n";
        std::cout << "2. Display All Students\n";
        std::cout << "3. Find Student by ID\n";
        std::cout << "4. Exit\n";
        std::cout << "Enter your choice: ";
        std::cin >> choice;

        switch (choice) {
            case 1:
                addStudent(students);
                break;
            case 2:
                displayAllStudents(students);
                break;
            case 3: {
                int id;
                std::cout << "Enter student ID: ";
                std::cin >> id;
                findStudentById(students, id);
                break;
            }
            case 4:
                std::cout << "Exiting the program." << std::endl;
                return 0;
            default:
                std::cout << "Invalid choice. Please try again." << std::endl;
        }
    }
}

总结

这个学生信息管理系统使用C++编写，展示了如何创建类、使用向量存储数据，以及实现一个简单的菜单驱动界面来添加、显示和查找学生信息。

关键字

C++, 学生信息管理系统, Student类, vector, 菜单驱动界面, 添加学生, 显示学生, 查找学生, 输入输出