파이썬 예외

예외처리(try ~ except)

def f(a, b): 

try: 

ifa andb: 

return(a * b) + (a / b) 

elifa: 

return '불능' 

else: 

return '부정' 

exceptErrorName: 

return '똑 바로 살아라'

 

예외발생시키기

   raise문에오류/예외의이름을넘길수있다.
 

class ShortInputException(Exception):
    length = 0
    atleast = 0
    '''A user-defined exception class.'''
    def __init__(self, length, atleast):
        Exception.__init__(self)
        self.length = length
        self.atleast = atleast



def exam():
	try:
		text = input('Enter something --> ')
		if len(text) <3:
			raise ShortInputException(len(text), 3)

	except EOFError:
		print( 'Why did you do an EOF on me?')
	except ShortInputException as ex:
		print('ShortInputException: The input was {0} long, expected at least {1}'.format(ex.length, ex.atleast))
	else:
		print('No exception was raised')


>>> exam()
Enter something --> a
ShortInputException: The input was 1 long, expected at least 3
>>> exam()
Enter something --> asdf
No exception was raised