python练习：学生管理系统

一、程序功能

1、功能介绍

• 利用python编写一个具有增、删、改、查的学生管理系统

2、思维导图

二、编写程序

1、首先写主程序（也就是一级菜单）

2、运行一下程序，查看结果

3、编辑二级菜单（函数模块化）

4、将文本文件链接到python中

5、完成程序的编写

三、对学生管理系统数据进行操作

1、增加学生记录

数据添加成功

2、删除学生记录

数据删除成功

3、修改学生记录

修改数据成功

4、查询学生记录

（1）按学号查询

（2）按姓名查询

四、原代码

def get_all_students():
    students = []
    f = open('学生.TXT')
    for line in f:
        line = line.replace('\n', '')
        student = line.split(' ')

        students.append(student)
    f.close() #关闭文件
    return students
# 增加学生记录
def add_student():
    students = get_all_students()
    id = input('学号:')
    name = input('姓名:')
    sex = input('性别:')
    age = input('年龄:')
    grade_class = input('班级:')
    major = input('专业:')
    college = input('学院:')
    phone_number = input('电话号码:')
    students.append([id, name,sex, age, grade_class,major, college,phone_number])

    f = open('学生.TXT','w')
    for i in range(len(students)):
        student = ' '.join(students[i])+ '\n'
        f.write(student)
    f.close() #关闭文件
    print('学生记录添加成功！')
# 查找学生记录
def query_student():
    while True:
        print("\n====学生管理系统====")
        print('1.按学号查询学生记录')
        print('2.按姓名查询学生记录')
        print('3.返回上级菜单')
        print('=' * 17)
        mc3 = int(input('输入菜单号：'))
        if mc3 == 1:
            student_number()
        elif mc3 == 2:
            student_name()

        else:
            break
def student_name():
    name = input('姓名: ')
    students = get_all_students()
    found = False
    for i in range(len(students)):
        if (students[i][1] == name):
            found = True
            for j in range(len(students[i])):
                print(students[i][j], end=' ')
            break
    if not found:
        print(f'学生信息中没有姓名为{name}的学生！')

# 按学号查找
def student_number():
    id = input('学号: ')
    found = False
    students = get_all_students()
    for i in range(len(students)):
        if students[i][0] == id:
            found = True
            for j in range(len(students[i])):
                print(students[i][j], end=' ')
            break
    if not found:
        print(f'学生信息中没有学号为{id}的学生!')

# 修改学生记录
def modify_student():
    students = get_all_students()
    id = input('需要修改信息的学生的学号: ')
    new_name = input('姓名: ')
    new_sex = input('性别: ')
    new_age = input('年龄: ')
    new_grade_class = input('班级: ')
    new_major = input('专业: ')
    new_college = input('学院: ')
    new_phone_number = input('电话号码: ')

    found = False
    for i in range(len(students)):
        if (students[i][0] == id):
            found = True
            students[i][1] = new_name
            students[i][2] = new_sex
            students[i][3] = new_age
            students[i][4] = new_grade_class
            students[i][5] = new_major
            students[i][6] = new_college
            students[i][7] = new_phone_number
            print('修改成功！')
            for j in range(len(students[i])):
                print(students[i][j], end=' ')
            break
    if not found:
        print(f'学生信息中没有学号为{id}的学生！')

    f = open('学生.TXT', 'w')
    for i in range(len(students)):
        student = ' '.join(students[i]) + '\n'
        f.write(student)
    f.close()  #关闭文件
# 删除学生记录
def delete_student():
    students = get_all_students()
    id = input('请输入要删除信息的学生的学号:')
    found = False
    for i in range(len(students)):
        if (students[i][0] == id):
            found = True
            break
    if not found:
        print(f'学生信息中没有学号为{id}的学生！')
    else:
        del students[i]
        print(f'学号为{id}已成功删除！')
    f = open('学生.TXT', 'w')
    for i in range(len(students)):
        student = ' '.join(students[i]) + '\n'

        f.write(student)
    f.close() #关闭文件
def login():
    username = input('请输入用户名: ')
    password = input('请输入密码: ')
    if username =='xxq' and password =='20021203':
        while True:
            print("\n====学生管理系统====")
            print('1.增加学生记录')
            print('2.查找学生记录')
            print('3.修改学生记录')
            print('4.删除学生记录')
            print('5.返回上一级菜单')
            print('=' * 17)
            mc2 = int(input('请输入菜单号：'))
            if mc2 == 1:
                add_student()
            elif mc2 == 2:
                query_student()
            elif mc2 == 3:
                modify_student()
            elif mc2 == 4:
                delete_student()
            else:
                break
    else:
         print('\n用户名或密码错误，请重新登录\n')
# 主程序
while True:
    print("\n====学生管理系统====")
    print('1.登录')
    print('2.退出')
    print('=' * 17)
    mc1 = int(input('请输入菜单号：'))
    if mc1 == 1:
        login()
    elif mc1 == 2:
        print('谢谢使用!')
        break
    else:
        print('请输入正确的菜单号')