python實現圖書管理系統

# 用戶註冊
def logon():
    print("歡迎來到圖書管理系統註冊頁面~")
    username = input("請輸入用戶名：")
    if len(username)<6:
        print("用戶名不能小於6個字符")
    else:
        email = input("請輸入郵箱：")
        password = input("請輸入密碼：")
        if len(password)<8:
            print("密碼不能少於8位")
        else:
            rpassword = input("請確認密碼：")
            if password ==rpassword:
                print("註冊成功！")
                # 函數調用，每追加一列數據都進行換行 每一個數據之間都有空格
                preserve_data(path,['\n'+ username,'   '+ email,'   '+ password])
                return True
            else:
                print("兩次輸入的密碼不一致，請從新輸入！")
                # 遞歸調用
                logon()


# 保存數據到文件
path = r'D:\Python\python-qf\文件操做\os.path\複製文件夾\案例練習\users\user.txt'
def preserve_data(file_path,data):
    # 將字符串轉換爲bytes，由於write寫入的是字節流，不能是字符串 當爲w時須要解碼
    # data = data.encode()
    # 打開文件，追加數據到文件
    with open(file_path,'a') as wstream:
        # 判斷是否可寫
        if wstream.writable():
            wstream.writelines(data)
        else:
            print("沒有權限！")


# 用戶登陸
def login():
    print("歡迎來到圖書管理系統登陸頁面~")
    tips = input("是否已經註冊？(yes/no)")
    if tips =='yes':
        while True:
            username = input("輸入用戶名：")
            password = input("輸入密碼：")
            # 讀取文件時可能會出現找不到文件的異常，所以使用try except
            try:
                # 讀取文件中的內容
                with open(path, 'rb') as stream:
                    # 讀取多行保存到列表中，列表中保存的是二進制，字節
                    result = stream.readlines()
                    # print(result)
                    # 列表推導式，循環遍歷列表，將字節解碼爲字符串放在一個新列表uesr_list
                    uesr_list = [i.decode() for i in result]
                    # print(uesr_list)
                    # 循環遍歷列表，檢查輸入的用戶名和密碼是否在字符串中
                    for i in uesr_list:
                        # print(i)
                        if username in i and password in i:
                            print("登陸成功")
                            operate(book_path,username)
                            break
                    else:
                        raise Exception("用戶名或密碼錯誤，請從新輸入！")

            except Exception as err:
                print(err)
            # 沒有異常時執行else語句
            else:
                break
    else:
        print("您還未註冊，請先註冊後再登陸！")
        # 遞歸
        logon()

# 查詢圖書
def find_books(path):
    try:
        with open(path, 'r') as rstream:
            # readlines讀到的內容是一個列表
            container = rstream.readlines()
            # 經過列表推導式獲得新的列表，即每一個元素去掉後面的換行符號
            new_container = [books_name.rstrip('\n') for books_name in container]
            for b_name in new_container:
                # 打印圖書+《》
                print("《{}》".format(b_name))

    except Exception as err:
        print("錯誤緣由：",err)

#添加圖書
def add_book(b_path,username):
    # 添加前首先判斷是不是管理員
    permission(b_path, username)
    # 追加圖書 不能是w ,不然會清空以前的內容
    with open(b_path, 'a') as wstream:
        # 判斷是否可寫
        if wstream.writable:
            msg = input("請輸入書名：")
            try:
                # 添加書籍以前判斷某本書是否已經添加
                with open(b_path) as rstream:
                    while True:
                        line = rstream.readline()
                        # 去掉右邊的換行
                        line = line.rstrip('\n')
                        # 當找到空行是若是尚未找到與輸入的書名一致的時候，就添加輸入的書名
                        if not line:
                            book = '\n' + msg
                            wstream.write(book)
                            print("添加成功")
                            break
                        else:
                            # 輸入的圖書和讀到的行有一致的則提示不能重複添加
                            if line == msg:
                                print("{}已添加,請不要重複添加哦~".format(msg))
                                break
            except Exception as err:
                print("錯誤緣由：", err)
        else:
            print("沒有權限")


# 修改圖書
def update_book(b_path,username):
    permission(b_path, username)
    try:
        with open(b_path, 'r') as rstream:
            container = rstream.read()
            # 經過'\n'來分割字符串，返回結果是列表
            container = container.split('\n')
            # print(container)
            # 刪除前先展現有哪些圖書
            find_books(book_path)
            book_name = input("請輸入須要修改的圖書書名：")
            # 循環遍歷修改書名
            for i in range(len(container)):
                if book_name == container[i]:
                    rbook_name = input("請輸入修改後的圖書書名：")
                    container[i] = rbook_name + '\n'
                else:
                    # 列表中的每一個書名後面加換行符，用於寫入文件時換行
                    container[i] = container[i] + '\n'
            # print(container)
            # 將書名更新後的內容以writelines寫入文件中  writelines(可迭代)
            with open(b_path, 'w') as wwstream:
                wwstream.writelines(container)
            print("修改爲功")
    except Exception as err:
        print("錯誤緣由：", err)



# 刪除圖書
def del_book(b_path,username):
    permission(path, username)
    try:
        with open(b_path, 'r') as rstream:
            container = rstream.read()
            # 經過'\n'來分割字符串，返回結果是列表
            container = container.split('\n')
            # print(container)
            # 展現有哪些圖書
            find_books(book_path)
            book_name = input("請輸入須要刪除的圖書書名：")
            # 循環遍歷修改書名
            for i in range(len(container) - 1):
                if book_name == container[i]:
                    container.remove(container[i])
                else:
                    # 列表中的每一個書名後面加換行符，用於寫入文件時換行
                    container[i] = container[i] + '\n'
            # print(container)
            # 將書名刪除後的內容以writelines寫入文件中  writelines(可迭代)
            with open(b_path, 'w') as wwstream:
                wwstream.writelines(container)
            print("刪除成功")
    except Exception as err:
        print("錯誤緣由：", err)

# 借書
def borrow_book(username):
    while True:
        print("圖書列表：")
        find_books(book_path)
        borrow_books = input("請選擇圖書：")
        try:
            with open('../user_books/user_books.txt') as rstream:
                # 每次讀取一行
                lines = rstream.readline()
                lines = lines.rstrip('\n')
                # 將讀到的內容經過空格分割保存到列表
                lines = lines.split(' ')
                # 判斷輸入的書是否已被借走
                if borrow_books not in lines:
                    # print(lines)
                    # 借書以前先判斷該用戶以前是否借過，若是借過，就在後面累加圖書，用，分割圖書
                    # for user_book in lines:
                    if username in lines:
                        with open('../user_books/user_books.txt', 'a') as wstream:
                            # 判斷以前是否借過某本書
                            if borrow_books not in lines:
                                wstream.write(' {}'.format(borrow_books))
                                print("借書成功")
                                break
                            else:
                                print("您已借過此書，請重新選擇！")
                                break
                    else:
                        # 將選擇的圖書與用戶名一塊兒保存到文件中
                        with open('../user_books/user_books.txt', 'a') as wstream:
                            wstream.write('\n{} {}\n'.format(username, borrow_books))
                            print("借書成功")
                            break
                else:
                    print("<<{}>>已被用戶{}借走，請從新選擇~".format(borrow_books,lines[0]))
        except Exception as err:
            print("錯誤緣由：", err)


# 還書
def return_book(username):
    try:
        with open('../user_books/user_books.txt') as rstream:
            # print("{}您已借閱，未歸還圖書以下：".format(username))
            # 讀到的結果是列表
            lines = rstream.readlines()
            # 遍歷列表，將裏面的元素再拆分爲列表
            for i in range(len(lines)):
                # 去掉換行
                lines[i] = lines[i].rstrip('\n')
                lines[i] = lines[i].rstrip(' ')
                lines[i] = lines[i].split(' ')
                for ii in range(len(lines[i])-1):
                    # 只打印登陸用戶借閱的圖書
                    if username == lines[i][0]:
                        print("{}您已借閱，未歸還圖書以下：".format(username))
                        print(lines[i][ii+1])
                        msg = input("請選擇你要歸還的圖書：")
                        with open('../user_books/user_books.txt') as rstream:
                            lines = rstream.readlines()
                            for i in range(len(lines)):
                                if username in lines[i] and msg in lines[i]:
                                    # 用空字符串替換msg,即表示刪除歸還的圖書
                                    lines[i] = lines[i].replace(msg, '')
                                    with open('../user_books/user_books.txt', 'w') as wstream:
                                        # 將變動後的列表再寫入文件，只變動當前用戶的圖書信息
                                        wstream.writelines(lines)
                                        print("歸還成功！")
                                        break

                            with open('../user_books/user_books.txt') as rstream:
                                lines = rstream.readlines()
                                for i in range(len(lines)):
                                    lines[i] = lines[i].rstrip('\n')
                                    lines[i] = lines[i].rstrip(' ')
                                    lines[i] = lines[i].split(' ')
                                    # print(type(lines[i]))
                                    for ii in range(len(lines[i])):
                                        # 圖書歸還成功後判斷列表中只有用戶名了，若是隻有用戶名則將用戶名用空字符串代替
                                        if username == lines[i][0] and len(lines[i]) == 1:
                                            lines[i][0] = lines[i][0].replace(lines[i][0], '')
                                            lines.append(lines[i][0])
                                # print(lines)
                                str = ''
                                for i in range(len(lines)):
                                    for ii in range(len(lines[i])):
                                        # 將嵌套列表中的元素取出來拼接成字符串
                                        str += lines[i][ii] + ' '
                                    str += '\n'
                                # 遍歷完畢刪除以前列表裏面嵌套的列表，追加字符串str
                                lines.clear()
                                lines.append(str)

                                # print(lines)
                                # 將更新後的列表寫入文件
                                with open('../user_books/user_books.txt', 'w') as wstream:
                                    wstream.writelines(lines)
                    else:
                        print("您尚未借閱記錄哦~")

    except Exception as err:
        print("錯誤緣由：", err)

# 查看我的信息
def look_person_info(path,username):
    with open(path) as rstream:
        while True:
            line = rstream.readline()
            if not line:
                break
            else:
                line = line.split('   ')
                # 列表推導式
                line = [info.strip('\n') for info in line]
                if username in line:
                    print("----我的信息----")
                    print("用戶名：",line[0])
                    print("郵箱：", line[1])
                    print("密碼：", line[2])


# 修改我的信息
def update_password(path,username):
    tips = input("請選擇操做：\n 1.修改郵箱\n 2.修改密碼\n")

    # 修改郵箱
    if tips =='1':
        new_email = ''
        line = []
        try:
            with open(path) as rstream:
                while True:
                    line = rstream.readline()
                    if not line:
                        break
                    line = line.split('   ')
                    # 去掉密碼後面的換行符
                    line[2] = line[2].rstrip('\n')
                    if username == line[0]:
                        new_email = input("請輸入新郵箱：")
                        line[1] = new_email
                        break
        except Exception as err:
            print(err)

        else:
            # 將新修改郵箱後的用戶的全部信息追加到文件夾
            with open(path, 'a') as wstream:
                for i in range(len(line)):
                    if i == 0:
                        # 遍歷列表，第一個列表元素須要前面須要加換行，後面須要加空格與其餘元素分割
                        line[i] = '\n' + line[i] + '   '
                    else:
                        line[i] = line[i] + '   '
                wstream.writelines(line)
                print("修改爲功")
            # 刪除修改郵箱以前用戶的信息
            with open(path) as rstream:
                # 讀取多行
                lines = rstream.readlines()
                i = 0
                l = len(lines)
                while i < l:
                    # 當 當前用戶名在用戶信息行且新的郵箱不在時就刪除以前的用戶信息，不會刪除其餘用戶的信息
                    if username in lines[i] and new_email not in lines[i]:
                        lines.remove(lines[i])
                    i += 1
                    l -= 1
                # 刪除舊郵箱對應的當前用戶信息後，再將新郵箱對應的用戶信息以及其餘用戶的信息重新寫入到文件
                with open(path, 'w') as wstream:
                    wstream.writelines(lines)
    # 修改密碼
    elif tips =='2':
        new_password = ''
        line = []
        try:
            with open(path) as rstream:
                while True:
                    line = rstream.readline()
                    if not line:
                        break
                    line = line.split('   ')
                    # 去掉密碼後面的換行符
                    line[2] = line[2].rstrip('\n')
                    if username == line[0]:
                        new_password = input("請輸入新密碼：")
                        # 判斷新密碼與舊密碼是否一致
                        if new_password ==line[2]:
                            # 拋出異常
                            raise Exception("新密碼不能與舊密碼相同哦~")
                        else:
                            line[2] =new_password
                            break
        # 能夠捕獲到前面raise拋出的異常
        except Exception as err:
            print(err)

        else:
            # 將新修改密碼後的用戶的全部信息追加到文件夾
            with open(path,'a') as wstream:
                for i in range(len(line)):
                    if i ==0:
                        # 遍歷列表，第一個列表元素須要前面須要加換行，後面須要加空格與其餘元素分割
                        line[i] = '\n'+line[i]+'   '
                    else:
                        line[i] = line[i] +'   '
                wstream.writelines(line)
                print("修改爲功")
            # 刪除修改密碼以前用戶的信息
            with open(path) as rstream:
                # 讀取多行
                lines = rstream.readlines()
                i =0
                l = len(lines)
                while i < l:
                    # 當 當前用戶名在用戶信息行且新的密碼不在時就刪除以前的用戶信息，不會刪除其餘用戶的信息
                    if username in lines[i] and new_password not in lines[i]:
                        lines.remove(lines[i])
                    i+=1
                    l-=1
                # 刪除舊密碼對應的當前用戶信息後，再將新密碼對應的用戶信息以及其餘用戶的信息重新寫入到文件
                with open(path,'w') as wstream:
                    wstream.writelines(lines)

# 我的信息
def person_information(path,username):
    tips = input("請選擇操做：\n 1.查看我的信息\n 2.修改我的信息\n")
    if tips =='1':
        look_person_info(path,username)
    elif tips =='2':
        update_password(path, username)

# 只有管理員才能夠進行圖書的增刪改操做
def permission(user_path,username):
    try:
        with open(user_path) as rstream:
            while True:
                line = rstream.readline()
                # 讀到空行跳出循環
                if not line:
                    break
                # 經過3個空格將字符串line分割爲一個列表，存儲三個值
                line = line.split('   ')
                # 循環遍歷列表，去掉列表中每一個元素後面的換行，若是有就去掉，沒有就不取掉
                for i in range(len(line)):
                    line[i] = line[i].rstrip('\n')
                # 判斷是否管理員，若是是就能夠進行添加操做
                if username == 'admin123':
                    pass
                else:
                    print("只有管理員才能夠進行該操做~".format(username))
                    # 不是管理員將回到操做頁面
                    operate(path, username)
    except Exception as err:
        print("錯誤緣由：",err)




# 圖書增刪改借還操做
book_path = '../books/books.txt'
# book_list = ['水滸傳\n','紅樓夢\n','廊橋遺夢']
def operate(b_path,username):
    while True:
        msg = input("請選擇操做:\n 1.查詢圖書\n 2.添加圖書\n 3.修改圖書\n 4.刪除圖書\n 5.借書\n 6.歸還圖書\n 7.我的信息\n 8.退出登陸\n")
        # 查詢圖書
        if msg =='1':
            find_books(book_path)
        # 添加圖書
        elif msg =='2':
            add_book(b_path, username)
        # 修改圖書
        elif msg =='3':
            update_book(b_path, username)
        # 刪除圖書
        elif msg =='4':
            del_book(b_path, username)
        # 借書
        elif msg =='5':
            borrow_book(username)
        # 還書
        elif msg =='6':
            return_book(username)
        #查看、修改我的信息
        elif msg =='7':
            person_information(path, username)

        # 退出登陸
        elif msg =='8':
            msg = input("肯定退出登陸嗎？(yes/no)")
            if msg == 'yes':
                break



login()