实现学生系统的增，删，查，打印所有学生功能，分别介绍使用列表存储和使用文件存储的代码

使用列表存储

import sys
students = []


def menu():
    print("1. 新增学生")
    print("2. 显示学生")
    print("3. 查找学生")
    print("4. 删除学生")
    print("0. 退出程序")
    choice = input("请输入您的操作>:")
    return int(choice)


def insert():
    print("开始新增学生！")
    name = input("请输入要增加学生的姓名>:")
    id = input("请输入要增加学生的学号>:")
    sex = input("请输入要增加学生的性别>: 男/女")

    if sex not in("男", "女"):
        print("输入的性别有错！")
        return
    classroom = input("请输入学生所在的班级>:")
    student = {
        "name": name,
        "id": id,
        "sex": sex,
        "classroom": classroom
    }
    global students
    students.append(student)


def show():
    for student in students:
        print(f"学生姓名：{student['name']} 学号：{student['id']} 性别：{student['sex']} 班级：{student['classroom']}")


def search():
    choice = int(input("请输入按姓名查找（1）/ 按学号查找（2）>: 1/2"))
    if choice == 1:
        name = input("请输入要查找的学生的姓名>:")
        for student in students:
            if student['name'] == name:
                print("找到了！")
                print(
                    f"学生姓名：{student['name']} 学号：{student['id']} 性别：{student['sex']} 班级：{student['classroom']}")
                return
            print("没找到")
            return
    else:
        id = input("请输入要查找的学生的学号>:")
        for student in students:
            if student['id'] == id:
                print("找到了！")
                print(
                    f"学生姓名：{student['name']} 学号：{student['id']} 性别：{student['sex']} 班级：{student['classroom']}")
                return
            print("没找到")
            return


def delete():
    choice = int(input("请输入按姓名删除（1）/ 按学号删除（2）>: 1/2"))
    if choice == 1:
        name = input("请输入要删除的学生的姓名>:")
        for student in students:
            if student['name'] == name:
                print("找到了！")
                print(
                    f"学生姓名：{student['name']} 学号：{student['id']} 性别：{student['sex']} 班级：{student['classroom']}")
                choice2 = int(input("确认删除请按1，否则按0>:"))
                if choice2 == 1:
                    students.remove(student)
                    return
            print("没找到")
            return
    else:
        id = input("请输入要删除的学生的学号>:")
        for student in students:
            if student['name'] == id:
                print("找到了！")
                print(
                    f"学生姓名：{student['name']} 学号：{student['id']} 性别：{student['sex']} 班级：{student['classroom']}")
                choice2 = int(input("确认删除请按1，否则按0>:"))
                if choice2 == 1:
                    students.remove(student)
                    return
            print("没找到")
            return


def main():
    print("---------------------------------")
    print("-----------学生管理系统------------")
    print("----student management system----")
    print("---------------------------------")

    while True:
        choice = menu()
        if choice == 1:
            insert()
        elif choice == 2:
            show()
        elif choice == 3:
            search()
        elif choice == 4:
            delete()
        elif choice == 0:
            print("退出程序！")
            sys.exit(0)
        else:
            print("输入错误，请输入0-4的数字！")


main()

使用文件存储

import os.path
import sys
students = []


def menu():
    print("1. 新增学生")
    print("2. 显示学生")
    print("3. 查找学生")
    print("4. 删除学生")
    print("0. 退出程序")
    choice = input("请输入您的操作>:")
    return int(choice)


def save():
    with open('students.txt', 'w', encoding='utf8') as f:
        for student in students:
            f.write(f"{student['name']}\t{student['id']}\t{student['sex']}\t{student['classroom']}\n")
        print(f"存档成功! 共存储了{len(student)}条数据")


def load():
    if not os.path.exists("students.txt"):
        return
    global students
    students = []
    with open("students.txt", "r", encoding="utf8") as f:
        for line in f:
            line = line.strip() # 去除字符串开头和末尾的空白符
            tokens = line.split("\t")
            if len(tokens) != 4:
                print(f"第{line}行数据出现格式错误！")
                continue
            student = {
                'id': tokens[0],
                'name': tokens[1],
                'sex': tokens[2],
                'classroom': tokens[3]
            }
            students.append(student)


def insert():
    print("开始新增学生！")
    name = input("请输入要增加学生的姓名>:")
    id = input("请输入要增加学生的学号>:")
    sex = input("请输入要增加学生的性别>: 男/女")

    if sex not in("男", "女"):
        print("输入的性别有错！")
        return
    classroom = input("请输入学生所在的班级>:")
    student = {
        "name": name,
        "id": id,
        "sex": sex,
        "classroom": classroom
    }
    global students
    students.append(student)
    save()


def show():
    for student in students:
        print(f"学生姓名：{student['name']} 学号：{student['id']} 性别：{student['sex']} 班级：{student['classroom']}")


def search():
    choice = int(input("请输入按姓名查找（1）/ 按学号查找（2）>: 1/2"))
    if choice == 1:
        name = input("请输入要查找的学生的姓名>:")
        for student in students:
            if student['name'] == name:
                print("找到了！")
                print(
                    f"学生姓名：{student['name']} 学号：{student['id']} 性别：{student['sex']} 班级：{student['classroom']}")
                return
            print("没找到")
            return
    else:
        id = input("请输入要查找的学生的学号>:")
        for student in students:
            if student['id'] == id:
                print("找到了！")
                print(
                    f"学生姓名：{student['name']} 学号：{student['id']} 性别：{student['sex']} 班级：{student['classroom']}")
                return
            print("没找到")
            return


def delete():
    choice = int(input("请输入按姓名删除（1）/ 按学号删除（2）>: 1/2"))
    if choice == 1:
        name = input("请输入要删除的学生的姓名>:")
        for student in students:
            if student['name'] == name:
                print("找到了！")
                print(
                    f"学生姓名：{student['name']} 学号：{student['id']} 性别：{student['sex']} 班级：{student['classroom']}")
                choice2 = int(input("确认删除请按1，否则按0>:"))
                if choice2 == 1:
                    students.remove(student)
                    save()
                    return
            print("没找到")
            return
    else:
        id = input("请输入要删除的学生的学号>:")
        for student in students:
            if student['name'] == id:
                print("找到了！")
                print(
                    f"学生姓名：{student['name']} 学号：{student['id']} 性别：{student['sex']} 班级：{student['classroom']}")
                choice2 = int(input("确认删除请按1，否则按0>:"))
                if choice2 == 1:
                    students.remove(student)
                    save()
                    return
            print("没找到")
            return


def main():
    load()
    print("---------------------------------")
    print("-----------学生管理系统------------")
    print("----student management system----")
    print("---------------------------------")

    while True:
        choice = menu()
        if choice == 1:
            insert()
        elif choice == 2:
            show()
        elif choice == 3:
            search()
        elif choice == 4:
            delete()
        elif choice == 0:
            print("退出程序！")
            sys.exit(0)
        else:
            print("输入错误，请输入0-4的数字！")


main()

可以看到，这时我们的程序中就有了students.txt