Python编程：从入门到实践的动手试一试答案（第十章）

#10-1 Python学习笔记with open('learning_python.txt') as file_object:    contents = file_object.read()    print(contents)----------------------------------------------with open('learning_python.txt') as file_object:    for line in file_object:        print(line.rstrip())----------------------------------------------with open('learning_python.txt') as file_object:    lines = file_object.readlines()for line in lines:    print(line.rstrip())

#10-2 C语言学习笔记with open('learning_python.txt') as file_object:    lines = file_object.readlines()for line in lines:    line1 = line.replace('Python','C')    print(line1.rstrip())

#10-3 访客filename = 'guest.txt'with open(filename,'w') as file_object:    name = input('请输入你的名字：')    file_object.write(name)

#10-4 访客名单filename = 'guest_book.txt'with open(filename,'a') as file_object:    print('按‘q’推出')    while True:        name = input('请输入你的名字：')        if name == 'q':            break        file_object.write(name + '\n')

#10-5 关于编程的调查filename = 'reason.txt'with open(filename,'a') as file_object:    print('按‘q’推出')    while True:        reason = input('请问你为何喜欢编程：')        if reason == 'q':            break        file_object.write(reason + '\n')

#10-6 加法运算try:    number1 = int(input('请输入一个数字：'))    number2 = int(input('请在输入一个数字：'))    result = number1 + number2    print(result)except ValueError:    print('你输入的格式有问题')

#10-7 加法计算器while True:    try:        number1 = int(input('请输入一个数字：'))        number2 = int(input('请在输入一个数字：'))        result = number1 + number2        print(result)    except ValueError:        print('你输入的格式有问题')

#10-8 猫和狗try:    with open('cats.txt') as cat:        print(cat.read())    with open('dogs.txt') as dog:        print(dog.read())except FileNotFoundError:    print('对不起没有找到文件')

#10-9 沉默的猫和狗try:    with open('cats.txt') as cat:        print(cat.read())    with open('dogs.txt') as dog:        print(dog.read())except FileNotFoundError:    pass

#10-10 常见单词try:    with open("The Girl Scouts' Canoe Trip by Edith Lavell.txt") as book:        content = book.read()        number = content.lower().count('the')        print(number)except FileNotFoundError:    pass

#10-11 喜欢的数字import jsonfilename = 'numbers.json'number = input('请输入你最喜欢的数字：')with open(filename, 'w') as f_obj:     json.dump(number, f_obj)with open(filename) as f_obj:     number = json.load(f_obj)     print('I know your favorite number! It is ___' + number)

#10-12 记住喜欢的数字import jsonfilename = 'numbers.json'try:        with open(filename) as f_obj:        number = json.load(f_obj)        print('I know your favorite number! It is ___' + number)except FileNotFoundError:    number = input('请输入你最喜欢的数字：')    with open(filename, 'w') as f_obj:        json.dump(number, f_obj)

#10-13 验证用户import jsondef get_stored_username():    """如果存储了用户名，就获取它"""    filename = 'username.json'    try:        with open(filename) as f_obj:            username = json.load(f_obj)    except FileNotFoundError:        return None    else:        return usernamedef get_new_username():    """提示用户输入用户名"""    username = input("What is your name? ")    filename = 'username.json'    with open(filename, 'w') as f_obj:        json.dump(username, f_obj)    return usernamedef greet_user():    """问候用户，并指出其名字"""    username = get_stored_username()    if username:        yep = input('Is ' + username + ' your name?(y/n)')        if  yep == 'y':            print("Welcome back, " + username + "!")        else:            username = get_new_username()            print("We'll remember you when you come back, " + username + "!")    else:        username = get_new_username()        print("We'll remember you when you come back, " + username + "!")greet_user()