python学习笔记（六）—— 错误处理

利用try-except代码块进行错误处理，避免崩溃。
try:
    print(5/0)
except ZeroDivisionError:
    print("You can't divide by zero!")

#使用异常避免崩溃
#try-except-else代码块
print("Give me two numbers,and I'll divide them")
print("Enter 'q' to quit")
while True:
    first_number = input("\nFirst number: ")
    if first_number == 'q':
        break
    second_number = input("Second number: ")
    try:
        answer = int(first_number)/int(second_number)
    except ZeroDivisionError:
        print("You can't divide by zero!")
    else:
        print(answer)




#处理找不到文件的异常
filename ='alice.txt'
try:
    with open(filename) as f_obj:
        contents = f_obj.read()
except FileNotFoundError:
    msg = "Sorrry,the file " + filename + " doesn't exist."
    print(msg)