文件和异常 10.1Python学习笔记
filename = 'learning_python.txt' with open(filename) as file_object: contents=file_object.read() print(contents) with open(filename) as file_object: for line in file_object: print(line.rstrip()) with open(filename) as file_object: lines=file_object.readlines() for line in lines: print(line.rstrip())10.2 C语言学习笔记
filename = 'learning_python.txt' with open(filename) as file_object: contents=file_object.read() print(contents) print(contents.replace('Python','C'))10.6加法运算
x=input("Give me a number:") y=input("Give me another number:") try: x_and_y=int(x)+int(y) except ValueError: print("You inter what is not number.") else: print("The sum of "+x+" and "+y+" is "+str(x_and_y)+'.')10.7加法计算器
print("Enter 'q' at anytime to quit.\n") while True: x=input("Give me a number:") if x == 'q': break y=input("Give me a number:") if y == 'q': break try: x_and_y=int(x)+int(y) except ValueError: print("You enter what is not number.") else: print("The sum of "+x+" and "+y+" is "+str(x_and_y)+'.')10.8猫和狗
def pets_name(pets): try: with open(pets) as file_object: contents=file_object.read() except FileNotFoundError: print("Sorry,the file "+pets+" does not exist.") else: cats_name=contents.split() for cat_name in cats_name: print("The pet's name is "+cat_name+".") cats='cats.txt' pets_name(cats) dogs='dogs.txt' pets_name(dogs)10.9沉默的猫和狗
def pets_name(pets): try: with open(pets) as file_object: contents=file_object.read() except FileNotFoundError: pass else: cats_name=contents.split() for cat_name in cats_name: print("The pet's name is "+cat_name+".") cats='cats.txt' pets_name(cats) dogs='dogs.txt' pets_name(dogs)10.10常见单词 好像是把所有有‘the’的单词也算进去了，暂时未找到解决的方法
def count_novels_the_number(novels): with open(novels) as file_object: novels_word=file_object.read() novel_the_number=novels_word.lower().count('the') print(novel_the_number) novels='siddhartha.txt' count_novels_the_number(novels) novels='alice.txt' count_novels_the_number(novels)10.11喜欢的数字
import json user_numbers='user_numbers.json' favorite_numbers=input("Enter your favorite number.") with open(user_numbers,'w') as file_object: json.dump(favorite_numbers,file_object) with open(user_numbers) as file_object: favorite_numbers=json.load(file_object) print(favorite_numbers)10.12记住喜欢的数字
import json user_numbers='user_numbers.json' try: with open(user_numbers) as file_object: favorite_numbers=json.load(file_object) except FileNotFoundError: favorite_numbers=input("Enter your favorite number.") with open(user_numbers,'w') as file_object: json.dump(favorite_numbers,file_object) else: print(favorite_numbers)10.13验证用户
import json def get_stored_username(): filename='user.json' try: with open(filename) as file_object: username=json.load(file_object) except FileNotFoundError: return None else: return username def get_new_username(): username=input("What is your name?") filename='user.json' with open(filename,'w') as file_object: json.dump(username,file_object) return username def greet_user(): username=get_stored_username() if username: correct=input("Are you "+username+"?(y/n)") if correct == 'y': print("Welcome back,"+username+".") else: username=get_new_username() print("We'll remember you when you come bake, "+username+"!") else: username=get_new_username() print("We'll remember you when you come bake, "+username+"!") greet_user()总结： 文件的读取、写入、代码出现异常的处理方法、使用json储存和读取数据；对代码的重构，把代码划分为多个函数，具体工作用具体函数，便于维护管理。
