“With”语句在Python中有多个文件可处理

Question

在这种情况下，我如何使用with语句？

f_spam = open(spam,'r') 
f_bar = open(eggs,'r') 
... 
do something with these files 
... 
f_spam.close() 
f_bar.close() 

文件编号可能大于2。

Answer 1

你也可以这样做：

from contextlib import nested 

with nested(open(spam), open(eggs)) as (f_spam, f_eggs): 
    # do something 

在Python 2.7和3.1+你不需要nested功能，因为with支持的语法如下：

with open(spam) as f_spam, open(eggs) as f_eggs: 
    # do something 

Answer 2

with open(spam,'r') as f_spam: 
    with open(eggs,'r') as f_bar: 
    #do stuff with each