Python编程 从入门到实践 第十章习题

10-1 Python学习笔记

filename = 'learning_python.txt'
print("读取整个文件：")
with open(filename) as file_object:
    contents = file_object.read()
    print(contents)

print("\n遍历文件对象：")
with open(filename) as file_object:
    for line in file_object:
        print(line.rstrip())

print("\n存储到列表：")
with open(filename) as file_object:
    lines = file_object.readlines()

for line in lines:
    print(line.rstrip())

输出：

读取整个文件：
In Python you can do web programs.
In Python you can do desktop software.
In Python you can develop network programs. 

遍历文件对象：
In Python you can do web programs.
In Python you can do desktop software.
In Python you can develop network programs.

存储到列表：
In Python you can do web programs.
In Python you can do desktop software.
In Python you can develop network programs.

10-3 访客：

filename = 'guest.txt'
name = ""
promt = "Tell me your name, or enter 'quit' to end the program: "
with open(filename, 'w') as file_object:
    while name != 'q':
        name = input(promt)
        if(name == 'q'):
            break
        else:
            print("Hello, " + name.title())
            file_object.write(name + "\n")

输出：

Tell me your name, or enter 'quit' to end the program: Alex
Hello, Alex
Tell me your name, or enter 'quit' to end the program: LEo
Hello, Leo
Tell me your name, or enter 'quit' to end the program: q

10-6 加法运算

def add():
    x = input("Please input the first number: ")
    y = input("Please input the second number: ")
    try:
        num1 = int(x)
        num2 = int(y)
    except ValueError:
        print("Some of your inputs is not a number! ")
    else:
        print(num1 + num2)

add()

输出：

Please input the first number: 34
Please input the second number: df
Some of your inputs is not a number! 

10-8 猫和狗

def pet(filename):
    try:
        with open(filename) as f_obj:
            contents = f_obj.read()
    except FileNotFoundError:
        msg = "\nSorry, the file " + filename + " dose not exist."
        print(msg)
    else:
        print("\n" + contents)


filenames = ["cat.txt", "bird.txt", "dog.txt"]
for filename in filenames:
    pet(filename)

输出：

Lili cat
NiNi cat
dongdong cat

Sorry, the file bird.txt dose not exist.

Alex dog
LEo dog
Mike dog

10-11 喜欢的数字：

import json

filename = 'number.json'
try:
    with open(filename) as f_obj:
        number = json.load(f_obj)
except FileNotFoundError:
    number = input("What is your favorite number ?")
    with open(filename, 'w') as f_obj:
        json.dump(number, f_obj)
        print("Welcome, we will remember your favorite number " + number)
else:
    print("Welcome back, your favorite number is " + number )

def get_number():
    with open(filename) as f_obj:
        print("I know your favorite number! It's " + json.load(f_obj))

get_number()

输出：

Welcome back, your favorite number is 12
I know your favorite number! It's 12