Simple, yet a little complicated library management system (python)

Note: The applications involved in this article are only for learning and communication. It is forbidden to use the technology in this article or the source code of the Github project associated with this article for any purpose.

Writing time: 2022.5.1 (Practice by yourself in freshman year)

Tools: pycharm python (idle) can be used normally

The content is simple and helps to master the reading and writing of the main content files of i/o. Although it is a bit more than 400 lines, they are all divided into function blocks

Every function is related, you can read and write slowly one by one, but the general idea remains the same, you can delete the unnecessary blocks by yourself, or you can make it simpler by yourself

can communicate

The following is each block

---

The file is read and named to facilitate subsequent writing (a total of three files are required)

# 图书登记
path_book = r'book.txt'
# 用户信息
path_users = r'users.txt'
# 借书登记
path_user_book = r'user_book.txt'

---

Check if there is such a user

# 注册系统
def register():
    print("--------------欢迎来到霁月的图书管理系统注册界面-------------")

    readUsers = open(path_users, 'r', encoding='utf-8')

    # 输入注册账号
    register_name = input("用户名:")
    while True:
        # 检查是否有该用户
        id = readUsers.readline()
        if register_name in id:
            print("用户以存在！")
            register_name = input("请重新输入用户名:")
        else:
            # 是否加上找回密码
            break

---

Mailbox writing

Can do password recovery and modification

    # 输入注册邮箱
    email = input("请输入邮箱:")
    while True:
        if not "@" in email:
            print("邮箱地址有错误")
            email = input("请重新输入:")
        else:
            break

---

Writing of registration password

    # 注册密码
    register_key = input("密码(只能由6--12位的数字或字母组成):")
    while True:
        # 检测密码正确性
        if (len(register_key) < 8) or (len(register_key)>12):
            print("名字格式错误")
            register_key = input("请重新输入密码:")

        register_password = input("请再次确定密码:")
        # 检查密码输入是否一致
        if register_key == register_password:
            with open('Users.txt', 'a', encoding='utf-8') as f:
                f.write('{}   {}   {} \n'.format(register_name, register_key, email))
                f.close()
            print('用户注册成功!')
            break
        else:
            print('密码不一致！')

    # 保存信息

---

login system

# 登录系统
def login():
    print("--------------欢迎来到霁月的图书管理系统登录界面-------------")
    # 打开文件检查 用户是否存在
    readUsers = open(path_users, 'r', encoding='utf-8')
    a = "1"

    # 输入账号密码
    username = input("账号:")
    password = input("密码:")

    # 检查 登录
    infos = readUsers.readlines()
    for info in infos:
        if info:
            if(username in info) and (password in info):
                print("--------------------登录成功-----------------------\n登录用户{}".format(username))
                operate_H(username)

            elif (username in info) or (password in info):
                print("账号或者密码错误,请重新输入!!!!!!")
                login()
                break
            else:
                a = "1"
                continue
    if a == "1":
        print("没有此账号请注册")
        register()

    # 返回用户名 方便之后的编写
    return username

---

Login screen for selecting

# 登录界面
def operate():
    print("-----------欢迎来到霁月的图书管理系统----------\n")
    print("1.登录\n2.注册\n3.退出")
    features = int(input("请输入你的选择:"))
    if features == 1:
        login()
    elif features == 2:
        register()
    elif features == 3:
        print("正在退出 。。。。。\n退出成功！")
    else:
        print("请输出正确的指令！")
        operate()

---

Function 1: query of books

# 图书查询
def search_book(username):
    with open(path_book, 'r', encoding='utf-8') as f:  # 取所有图书信息
        books_inf = f.readlines()
    print('编号'.center(5, ' '), '书名'.center(15, ' '), '作者'.center(15, ' '), '种类'.center(15, ' '), '状态'.center(15, ' '))
    format_data = '{:^5}\t{:^15}\t{:^15}\t{:^14}\t{:^15}'
    for temp in books_inf:
        b = eval(temp)
        print(format_data.format(b.get('编号'), b.get('书名'), b.get('作者'), b.get('种类'), b.get('状态')))
        operate_H(username)

---

Function 2: The borrowing module is divided into two for easy viewing

# 借书模块
def borrow_book(username):
    borrow_book1 = input("请输入你要借阅的图书:")
    a = "0"
    if borrow_book1 == "111":
        operate_H(username)
    with open(path_book, 'r', encoding='utf-8') as f:  # 取所有图书信息
        # 遍历图书
        books_inf = f.readlines()
        for book_inf in books_inf:
            book = eval(book_inf)
            book = book.get('书名')

            if book == borrow_book1:
                a = "0"
                borrow_book2(username, borrow_book1)
                break
            else:
                a = "1"
        if a == "1":
            print("没有你要找的书")
            borrow_book(username)

def borrow_book2(username, borrow_book1):

    with open(path_user_book, "r", encoding="utf-8") as f:
        uses = f.readlines()
        a = "1"
        for use in uses:
            # 借过这本书
            if (username in use) and (borrow_book1 in use):
                a = "0"
                print("你以借过此书")
                borrow_book(username)
                break
            # 书被借走了
            elif(borrow_book1 in use) and (username not in use):
                a = "0"
                print("书已被别人借走")
                borrow_book(username)
                break
            else:
                a = "1"
                continue

---

Function 3: Return Books

# 还书
def return_book(username):
    return_book1 = input("请输入你要归还的图书:")
    a = "0"
    if return_book1 == "111":
        operate_H(username)
    with open(path_book, 'r', encoding='utf-8') as f:  # 取所有图书信息
        # 遍历图书
        books_inf = f.readlines()
        for book_inf in books_inf:
            book = eval(book_inf)
            book = book.get('书名')

            if book == return_book1:
                a = "0"
                return_book2(username, return_book1)
                break
            else:
                a = "1"
        if a == "1":
            print("图书馆没有此书")
            return_book(username)

def return_book2(username, return_book1):
    with open(path_user_book, "r", encoding="utf-8") as f:
        uses = f.readlines()
        a = "1"
        # 除去文件中书的记录
        with open(path_user_book, "w", encoding="utf-8") as w:
            for use in uses:
                if (username in use) and (return_book1 in use):
                    continue
                else:
                    w.writelines(use)
                    w.close()
        f.close()

        print("--------------{}已将{}归还--------------------".format(username, return_book1))
        print("归还成功")
        # 遍历还未归还的书籍
        with open(path_user_book, "r", encoding="utf-8") as g:
            uses = g.readlines()
            for use in uses:
                if username in use:
                    print("未归还"+use)
                    g.close()
        operate_H(username)

---

Function 4: Modify user information

# 修改个人信息
def update_password(username):
    tips = input("\n 1.修改邮箱\n 2.修改密码\n请选择操作:")
    if tips == "111":
        operate_H(username)

    # 修改邮箱
    if tips == '1':
        new_email = ''
        line = []
        try:
            with open(path_users, encoding='utf-8') as rstream:
                while True:
                    line = rstream.readline()
                    if not line:
                        break
                    line = line.split('   ')
                    # 去掉密码后面的换行符
                    line[1] = line[1].rstrip('\n')
                    if username == line[0]:
                        new_email = input("请输入新邮箱:")
                        line[2] = new_email
                        break
        except Exception as err:
            print(err)

        else:
            # 将新修改邮箱后的用户的所有信息追加到文件夹
            with open(path_users, 'a', encoding='utf-8') as wstream:
                for i in range(len(line)):
                    if i == 0:
                        # 遍历列表，第一个列表元素需要前面需要加换行，后面需要加空格与其他元素分割
                        line[i] = '\n' + line[i] + '   '
                    else:
                        line[i] = line[i] + '   '
                wstream.writelines(line)
                print("修改成功")
            # 删除修改邮箱之前用户的信息
            with open(path_users, encoding='utf-8') as rstream:
                # 读取多行
                lines = rstream.readlines()
                i = 0
                l = len(lines)
                while i < l:
                    # 当前用户名在用户信息行且新的邮箱不在时就删除之前的用户信息，不会删除其他用户的信息
                    if username in lines[i] and new_email not in lines[i]:
                        lines.remove(lines[i])
                    i += 1
                    l -= 1
                # 删除旧邮箱对应的当前用户信息后，再将新邮箱对应的用户信息以及其他用户的信息从新写入到文件
                with open(path_users, 'w', encoding='utf-8') as wstream:
                    wstream.writelines(lines)
    # 修改密码
    elif tips == '2':
        new_password = ''
        line = []
        try:
            with open(path_users, encoding='utf-8') as rstream:
                while True:
                    line = rstream.readline()
                    if not line:
                        break
                    line = line.split('   ')
                    # 去掉密码后面的换行符
                    line[1] = line[1].rstrip('\n')
                    if username == line[0]:
                        new_password = input("请输入新密码：")
                        # 判断新密码与旧密码是否一致
                        if new_password == line[1]:
                            # 抛出异常
                            raise Exception("新密码不能与旧密码相同哦~")
                        else:
                            line[1] = new_password
                            break
        # 可以捕获到前面raise抛出的异常
        except Exception as err:
            print(err)

        else:
            # 将新修改密码后的用户的所有信息追加到文件夹
            with open(path_users, 'a', encoding='utf-8') as wstream:
                for i in range(len(line)):
                    if i == 0:
                        # 遍历列表，第一个列表元素需要前面需要加换行，后面需要加空格与其他元素分割
                        line[i] = '\n' + line[i] + '   '
                    else:
                        line[i] = line[i] + '   '
                wstream.writelines(line)
                print("修改成功")
            # 删除修改密码之前用户的信息
            with open(path_users, encoding='utf-8') as rstream:
                # 读取多行
                lines = rstream.readlines()
                i = 0
                l = len(lines)
                while i < l:
                    # 当 当前用户名在用户信息行且新的密码不在时就删除之前的用户信息，不会删除其他用户的信息
                    if username in lines[i] and new_password not in lines[i]:
                        lines.remove(lines[i])
                    i += 1
                    l -= 1
                # 删除旧密码对应的当前用户信息后，再将新密码对应的用户信息以及其他用户的信息从新写入到文件
                with open(path_users, 'w', encoding='utf-8') as wstream:
                    wstream.writelines(lines)
                    operate_H(username)

---

view personal information

# 查看个人信息
def look_person_info(username):
    with open(path_users, encoding="utf-8") as rstream:
        lines = rstream.readlines()
        for info in lines:
            # 分割成一个列表
            info = info.split('   ')
            # print(info)
            if username in info:
                print("----个人信息----")
                print("用户名：", info[0])
                print("密码：", info[1])
                print("邮箱：", info[2].rstrip(' '))
                person_information(username)

---

Interface of function 4

# 个人信息的查询和修改
def person_information(username):
    # 信息选择
    tips = input(" 1.查看个人信息\n 2.修改个人信息\n请选择操作:")
    if tips == '1':
        look_person_info(username)
    elif tips == '2':
        update_password(username)

---

Function 5: Add books (I wanted to add an administrator) but there are too many and I am too lazy to write

You can improve it by yourself: you can send it to me for use

# 添加图书 （管理员）
def add_book():
    id_book = int(input('请输入编号:'))
    name_book = input('请输入书名:')
    author_book = input('请输入作者:')
    type_book = input('请输入种类:')
    state_book = input('请输入图书状态:')
    book_information = {'编号': id_book, '书名': name_book, '作者': author_book, '种类': type_book, '状态':state_book}
    with open(path_book, 'a', encoding='utf-8') as f:
        f.write(str(book_information))
        f.write('\n')

---

Large interface for selecting functions

# 主功能页面
def operate_H(username):
    features = int(input("选择你要的功能(0 可打开菜单):"))
    if features == 0:
        menu(username)
    elif features == 1:
        borrow_book(username)
    elif features == 2:
        return_book(username)
        # 归还图书
    elif features == 3:
        search_book(username)
    elif features == 4:
        person_information(username)
    elif features == 5:
        pass
    elif features == 22:
        add_book()
    else:
        print("请不要输入无效信息")
        operate_H(username)
        # 查询个人信息

---

Startup function (required)

# 启动
if __name__ == '__main__':
    operate()


# 有机会加上 图书状态 函数跳跃
# 添加管理员查询借书信息
# 添加管理员可视化借书浮动与数据比较
# 加上可视化界面
# 连接笔趣阁 利用爬虫真正获取图书信息

---

full code

# 大纲 全部内容
# 界面 ；登录 注册 选项
# 普通人 ： 借书 还书 查询书籍 账号管理 退出系统
# 管理员； 查询 添加书本 删除 个人信息
# 储存文件；借书登记 图书库 用户信息


# 文件存放位置

# 书本

# 地址

path_book = r'book.txt'
# 用户信息
path_users = r'users.txt'
# 借书登记
path_user_book = r'user_book.txt'



# 注册系统
def register():
    print("--------------欢迎来到霁月的图书管理系统注册界面-------------")

    readUsers = open(path_users, 'r', encoding='utf-8')

    # 输入注册账号
    register_name = input("用户名:")
    while True:
        # 检查是否有该用户
        id = readUsers.readline()
        if register_name in id:
            print("用户以存在！")
            register_name = input("请重新输入用户名:")
        else:
            # 是否加上找回密码
            break


    # 输入注册邮箱
    email = input("请输入邮箱:")
    while True:
        if not "@" in email:
            print("邮箱地址有错误")
            email = input("请重新输入:")
        else:
            break


    # 注册密码
    register_key = input("密码(只能由6--12位的数字或字母组成):")
    while True:
        # 检测密码正确性
        if (len(register_key) < 8) or (len(register_key)>12):
            print("名字格式错误")
            register_key = input("请重新输入密码:")

        register_password = input("请再次确定密码:")
        # 检查密码输入是否一致
        if register_key == register_password:
            with open('Users.txt', 'a', encoding='utf-8') as f:
                f.write('{}   {}   {} \n'.format(register_name, register_key, email))
                f.close()
            print('用户注册成功!')
            break
        else:
            print('密码不一致！')

    # 保存信息



# 登录系统
def login():
    print("--------------欢迎来到霁月的图书管理系统登录界面-------------")
    # 打开文件检查 用户是否存在
    readUsers = open(path_users, 'r', encoding='utf-8')
    a = "1"

    # 输入账号密码
    username = input("账号:")
    password = input("密码:")

    # 检查 登录
    infos = readUsers.readlines()
    for info in infos:
        if info:
            if(username in info) and (password in info):
                print("--------------------登录成功-----------------------\n登录用户{}".format(username))
                operate_H(username)

            elif (username in info) or (password in info):
                print("账号或者密码错误,请重新输入!!!!!!")
                login()
                break
            else:
                a = "1"
                continue
    if a == "1":
        print("没有此账号请注册")
        register()

    # 返回用户名 方便之后的编写
    return username


# 登录界面
def operate():
    print("-----------欢迎来到霁月的图书管理系统----------\n")
    print("1.登录\n2.注册\n3.退出")
    features = int(input("请输入你的选择:"))
    if features == 1:
        login()
    elif features == 2:
        register()
    elif features == 3:
        print("正在退出 。。。。。\n退出成功！")
    else:
        print("请输出正确的指令！")
        operate()




# 图书查询
def search_book(username):
    with open(path_book, 'r', encoding='utf-8') as f:  # 取所有图书信息
        books_inf = f.readlines()
    print('编号'.center(5, ' '), '书名'.center(15, ' '), '作者'.center(15, ' '), '种类'.center(15, ' '), '状态'.center(15, ' '))
    format_data = '{:^5}\t{:^15}\t{:^15}\t{:^14}\t{:^15}'
    for temp in books_inf:
        b = eval(temp)
        print(format_data.format(b.get('编号'), b.get('书名'), b.get('作者'), b.get('种类'), b.get('状态')))
        operate_H(username)



# 借书模块
def borrow_book(username):
    borrow_book1 = input("请输入你要借阅的图书:")
    a = "0"
    if borrow_book1 == "111":
        operate_H(username)
    with open(path_book, 'r', encoding='utf-8') as f:  # 取所有图书信息
        # 遍历图书
        books_inf = f.readlines()
        for book_inf in books_inf:
            book = eval(book_inf)
            book = book.get('书名')

            if book == borrow_book1:
                a = "0"
                borrow_book2(username, borrow_book1)
                break
            else:
                a = "1"
        if a == "1":
            print("没有你要找的书")
            borrow_book(username)

def borrow_book2(username, borrow_book1):

    with open(path_user_book, "r", encoding="utf-8") as f:
        uses = f.readlines()
        a = "1"
        for use in uses:
            # 借过这本书
            if (username in use) and (borrow_book1 in use):
                a = "0"
                print("你以借过此书")
                borrow_book(username)
                break
            # 书被借走了
            elif(borrow_book1 in use) and (username not in use):
                a = "0"
                print("书已被别人借走")
                borrow_book(username)
                break
            else:
                a = "1"
                continue

        # 借书成功
        if a == "1":
            with open(path_user_book, "a", encoding="utf-8") as g:
                g.writelines("{} {}\n".format(username, borrow_book1))
                print("借书成功")
                g.close()
                operate_H(username)



# 还书
def return_book(username):
    return_book1 = input("请输入你要归还的图书:")
    a = "0"
    if return_book1 == "111":
        operate_H(username)
    with open(path_book, 'r', encoding='utf-8') as f:  # 取所有图书信息
        # 遍历图书
        books_inf = f.readlines()
        for book_inf in books_inf:
            book = eval(book_inf)
            book = book.get('书名')

            if book == return_book1:
                a = "0"
                return_book2(username, return_book1)
                break
            else:
                a = "1"
        if a == "1":
            print("图书馆没有此书")
            return_book(username)

def return_book2(username, return_book1):
    with open(path_user_book, "r", encoding="utf-8") as f:
        uses = f.readlines()
        a = "1"
        # 除去文件中书的记录
        with open(path_user_book, "w", encoding="utf-8") as w:
            for use in uses:
                if (username in use) and (return_book1 in use):
                    continue
                else:
                    w.writelines(use)
                    w.close()
        f.close()

        print("--------------{}已将{}归还--------------------".format(username, return_book1))
        print("归还成功")
        # 遍历还未归还的书籍
        with open(path_user_book, "r", encoding="utf-8") as g:
            uses = g.readlines()
            for use in uses:
                if username in use:
                    print("未归还"+use)
                    g.close()
        operate_H(username)



# 修改个人信息
def update_password(username):
    tips = input("\n 1.修改邮箱\n 2.修改密码\n请选择操作:")
    if tips == "111":
        operate_H(username)

    # 修改邮箱
    if tips == '1':
        new_email = ''
        line = []
        try:
            with open(path_users, encoding='utf-8') as rstream:
                while True:
                    line = rstream.readline()
                    if not line:
                        break
                    line = line.split('   ')
                    # 去掉密码后面的换行符
                    line[1] = line[1].rstrip('\n')
                    if username == line[0]:
                        new_email = input("请输入新邮箱:")
                        line[2] = new_email
                        break
        except Exception as err:
            print(err)

        else:
            # 将新修改邮箱后的用户的所有信息追加到文件夹
            with open(path_users, 'a', encoding='utf-8') as wstream:
                for i in range(len(line)):
                    if i == 0:
                        # 遍历列表，第一个列表元素需要前面需要加换行，后面需要加空格与其他元素分割
                        line[i] = '\n' + line[i] + '   '
                    else:
                        line[i] = line[i] + '   '
                wstream.writelines(line)
                print("修改成功")
            # 删除修改邮箱之前用户的信息
            with open(path_users, encoding='utf-8') as rstream:
                # 读取多行
                lines = rstream.readlines()
                i = 0
                l = len(lines)
                while i < l:
                    # 当前用户名在用户信息行且新的邮箱不在时就删除之前的用户信息，不会删除其他用户的信息
                    if username in lines[i] and new_email not in lines[i]:
                        lines.remove(lines[i])
                    i += 1
                    l -= 1
                # 删除旧邮箱对应的当前用户信息后，再将新邮箱对应的用户信息以及其他用户的信息从新写入到文件
                with open(path_users, 'w', encoding='utf-8') as wstream:
                    wstream.writelines(lines)
    # 修改密码
    elif tips == '2':
        new_password = ''
        line = []
        try:
            with open(path_users, encoding='utf-8') as rstream:
                while True:
                    line = rstream.readline()
                    if not line:
                        break
                    line = line.split('   ')
                    # 去掉密码后面的换行符
                    line[1] = line[1].rstrip('\n')
                    if username == line[0]:
                        new_password = input("请输入新密码：")
                        # 判断新密码与旧密码是否一致
                        if new_password == line[1]:
                            # 抛出异常
                            raise Exception("新密码不能与旧密码相同哦~")
                        else:
                            line[1] = new_password
                            break
        # 可以捕获到前面raise抛出的异常
        except Exception as err:
            print(err)

        else:
            # 将新修改密码后的用户的所有信息追加到文件夹
            with open(path_users, 'a', encoding='utf-8') as wstream:
                for i in range(len(line)):
                    if i == 0:
                        # 遍历列表，第一个列表元素需要前面需要加换行，后面需要加空格与其他元素分割
                        line[i] = '\n' + line[i] + '   '
                    else:
                        line[i] = line[i] + '   '
                wstream.writelines(line)
                print("修改成功")
            # 删除修改密码之前用户的信息
            with open(path_users, encoding='utf-8') as rstream:
                # 读取多行
                lines = rstream.readlines()
                i = 0
                l = len(lines)
                while i < l:
                    # 当 当前用户名在用户信息行且新的密码不在时就删除之前的用户信息，不会删除其他用户的信息
                    if username in lines[i] and new_password not in lines[i]:
                        lines.remove(lines[i])
                    i += 1
                    l -= 1
                # 删除旧密码对应的当前用户信息后，再将新密码对应的用户信息以及其他用户的信息从新写入到文件
                with open(path_users, 'w', encoding='utf-8') as wstream:
                    wstream.writelines(lines)
                    operate_H(username)

# 查看个人信息
def look_person_info(username):
    with open(path_users, encoding="utf-8") as rstream:
        lines = rstream.readlines()
        for info in lines:
            # 分割成一个列表
            info = info.split('   ')
            # print(info)
            if username in info:
                print("----个人信息----")
                print("用户名：", info[0])
                print("密码：", info[1])
                print("邮箱：", info[2].rstrip(' '))
                person_information(username)

# 个人信息的查询和修改
def person_information(username):
    # 信息选择
    tips = input(" 1.查看个人信息\n 2.修改个人信息\n请选择操作:")
    if tips == '1':
        look_person_info(username)
    elif tips == '2':
        update_password(username)



# 菜单
def menu(username):
    print("----------------- 菜单 ------------------------")
    print("1.借书\n2.还书\n3.查看全部书籍\n4.个人信息\n5.退出")
    operate_H(username)



# 添加图书 （管理员）
def add_book():
    id_book = int(input('请输入编号:'))
    name_book = input('请输入书名:')
    author_book = input('请输入作者:')
    type_book = input('请输入种类:')
    state_book = input('请输入图书状态:')
    book_information = {'编号': id_book, '书名': name_book, '作者': author_book, '种类': type_book, '状态':state_book}
    with open(path_book, 'a', encoding='utf-8') as f:
        f.write(str(book_information))
        f.write('\n')


# 主功能页面
def operate_H(username):
    features = int(input("选择你要的功能(0 可打开菜单):"))
    if features == 0:
        menu(username)
    elif features == 1:
        borrow_book(username)
    elif features == 2:
        return_book(username)
        # 归还图书
    elif features == 3:
        search_book(username)
    elif features == 4:
        person_information(username)
    elif features == 5:
        pass
    elif features == 22:
        add_book()
    else:
        print("请不要输入无效信息")
        operate_H(username)
        # 查询个人信息



# 启动
if __name__ == '__main__':
    operate()


# 有机会加上 图书状态 函数跳跃
# 添加管理员查询借书信息
# 添加管理员可视化借书浮动与数据比较
# 加上可视化界面
# 连接笔趣阁 利用爬虫真正获取图书信息