异常处理

--raise

>>> raise IOError('This is a test!')

Traceback (most recent call last):

File "<pyshell#0>", line 1, in <module>

raise IOError('This is a test!')

OSError: This is a test!

 

--try except

def get_age():

while True:

try:

n = int(input('How old are you? '))

return n

except ValueError:

print('Please enter an integer value.')

 

运行结果：

>>> get_age()

How old are you? 30

30

>>> get_age()

How old are you? aaa

Please enter an integer value.

How old are you? 28

28

 

--捕获多种异常

try:

语句

except(ValueError, TypeError):

语句

 

try:

语句

except ValueError:

语句

except TypeError:

语句

 

--捕获所有异常

try:

语句

except:

语句

 

--清理操作

try:

语句

except:

语句

finally:

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