#1.python学习笔记：在文本编辑器中新创建一个文件，写几句话老总结你至此学到的python知识 #其中‘In Python you can’ 打头。将这个文件命名为learning_python.txt.并将其存储到为本章学习目录下 #编写一个程序，它读取这个文件，并将你序偶写的内容打印三次：第一次打印时读取整个文件 #第二次打印时遍历文件对象，第三次打印时将各行存储在一个列表中，再在with代码块外打印它们with open('learning_python.txt') as file_object:contents = file_object.read()print(contents)filename = 'learning_python.txt'with open(filename) as file_object1:for line in file_object1:print(line.rstrip())print('\n') with open(filename) as file_object2:lines = file_object2.readlines()for line in lines:print(line.rstrip())print('\n') #2.在1中完成的基础上，使用方法replace()将learning_python.txt中的Python替换成其它任意一门语言 filename = 'learning_python.txt' with open(filename) as file_object1:for line in file_object1:line = line.replace('Python','Java')print(line.rstrip()) #1.访客：编写一个程序，提示用户输入其名字；用户作出响应后，将其名字写入到文件guest.txt中guest_names = input("Enter your name: ") with open('guest.txt','a') as file_object:file_object.write(guest_names + '\n')#2.访问名单：编写一个while循环，提示用户输入其名字。用户输入其名字后，在屏幕打印一句问候语 #并将一条访问记录添加到文件guest_book.txt中。确保这个文件中的每条记录都独占一行while True:print("Enter a to quit.")names = input("Enter your name: ")if names == 'q':breakmessages = "Hello! " + namesprint(messages)with open('guest_book.txt','a') as file_object:file_object.write(messages + '\n')#3.关于编程的调查：编写一个while循环，询问用户为何喜欢编程。每当用户输入一个原因后， #都将其添加到一个存储所有原因的文件中while True:print("Enter q to quit.")reasons = input("Why do you like programming? ")if reasons == 'q':breakwith open('reason_books.txt','a') as file_object:file_object.write(reasons + '\n')#1.加法运算：提示用户提供数值输入时，常出现的一个问题是，用户提供的是文本而不是数字 #在这种情况下，当你尝试将输入转换为整数时，将引发TypeError异常。 #编写一个程序，提示用户输入两个数字，再将它们相加并打印结果。在用户输入的任一个值不是 #数字时都铺获TypeError异常，并打印一条友好的错误消息。while True:try:first_number = int(input("Enter to the first number: "))second_number = int(input("Enter to the second number: "))sum = first_number + second_numberexcept ValueError:print("Sorry,TypeError! please input again."else:print("The add result of two numbers:",sum)#2.猫和狗：创建两个文件cat.txt和dog.txt，在第一个文件中至少存储三只猫的名字 #在第二个文件中至少存储三条狗的名字。编写一个程序，尝试读取这些文件， #并将其内容打印到屏幕上。将这些代码放在一个try-except代码块中，以便文件 #不存在是捕获FileNotFound错误，并打印一条友好的消息，将其中一个文件移到另一个 #地方，并确认except代码块中的代码将正确执行。def Openfile(filename):try: with open(filename) as file_read:contents = file_read.read()print(contents.rstrip())except FileNotFoundError:print("Sorry,The file " + filename + " does not exit!")filename = 'alice.txt' Openfile(filename) filename ='dog.txt' Openfile(filename)#3.修改在2中所编写的except代码块，让程序不存在时一言不发def Openfile(filename):try: with open(filename) as file_read:contents = file_read.read()print(contents.rstrip())except FileNotFoundError:passfilename = 'alice.txt' Openfile(filename) filename ='dog.txt' Openfile(filename)#4.常见单词：找一些你想分析的图书，使用方法count()来确定特定单词或短语在字符串中出现的次数 def Ludong(filename):try:with open(filename) as file_object:contents = file_object.read()print(contents.rstrip())print("The word appears " + str(contents.lower().count('ludong')) + " times.")except FileNotFoundError:print("The file " + filename + " does not exit!")filename = 'ludong.txt' Ludong(filename) #1.喜欢的数字：编写一个程序，提示用户输入他喜欢的数字，并使用 #json.dump()将这个数字存储到文件中。再编写一个程序，从文件中读取这个值 #并打“I know your favorite number! It's 。。 import jsondef StoreNumber():#如果存储数字就获取它filename = 'usernumber.json'try:with open(filename) as f_obj:usernumber = json.load(f_obj)except FileNotFoundError:return Noneelse:return usernumberdef get_new_number():#提示用户输入数字usernumber = input("Enter to your favorite number: ")filename = 'usernumber.json'with open(filename,'w') as f_obj:json.dump(usernumber,f_obj)return usernumberdef ReadNumber():#读取数字usernumber = StoreNumber()if usernumber:print("I Know your favorite number! It's " + str(usernumber))else:usernumber = get_new_number()print("I'll remember the number: " + str(usernumber))ReadNumber()#2.验证用户：最后一个remember_me.py版本假设用户要么已输入其用户名，要么是首次运行改程序。 #我们应修改这个程序，应对这样的情形：当前和最后一次运行该程序的用户并非同一个人 #因此，在greet_user()中打印欢迎用户回来的消息前，先询问用户名是否是对的 #如果不对，就调用get_new_username()让用户输入正确的用户名 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 Noneelse:return usernamedef get_new_user():#提示用户输入名字username = input("What's 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username = get_stored_username()if username:ask = "Your username is " + username +"?"+ "if not,please input N, "ask += "if yes,input Y: "ask_msg = input(ask)if ask_msg == 'Y':print("Welcome back," + username + '!')else:username = get_new_user() print("We'll remember you when you come back, " + username + '!')else:username = get_new_user() print("We'll remember you when you come back, " + username + '!')greet_user()