我有一个像这样的字符串：
>>> s = '1,",2, ",,4,,,\',7, \',8,,10,'
>>> s
'1,",2, ",,4,,,\',7, \',8,,10,'
我想使用不同的定界符（not just white spaces）对其进行拆分，并且我还希望尊重和保留引号（单引号或双引号）。
在定界符s上分割,时的预期结果：
['1', ',2, ', '', '4', '', '', ',7, ', '8', '', '10', '']
答案 0 :(得分：2)
您似乎正在重新发明python模块csv。包括电池。
In [1]: import csv
In [2]: s = '1,",2, ",,4,,,\',7, \',8,,10,'
In [3]: next(csv.reader([s]))
Out[3]: ['1', ',2, ', '', '4', '', '', "'", '7', " '", '8', '', '10', '']
我认为，正则表达式通常不是很好的解决方案。在意外的时刻，它可能会出奇地慢。在csv模块中，可以调整方言，并且很容易处理字符串/文件的任何数字。
我无法同时将csv调整为quotechar的两个变体，但是您真的需要吗？
In [4]: next(csv.reader([s], quotechar="'"))
Out[4]: ['1', '"', '2', ' "', '', '4', '', '', ',7, ', '8', '', '10', '']
或
In [5]: s = '1,",2, ",,4,,,",7, ",8,,10,'
In [6]: next(csv.reader([s]))
Out[6]: ['1', ',2, ', '', '4', '', '', ',7, ', '8', '', '10', '']
答案 1 :(得分：0)
this的修改版本（仅处理空白）可以解决问题（引号被删除）：
>>> import re
>>> s = '1,",2, ",,4,,,\',7, \',8,,10,'
>>> tokens = [t for t in re.split(r",?\"(.*?)\",?|,?'(.*?)',?|,", s) if t is not None ]
>>> tokens
['1', ',2, ', '', '4', '', '', ',7, ', '8', '', '10', '']
如果您想保留引号，请输入以下字符：
>>> tokens = [t for t in re.split(r",?(\".*?\"),?|,?('.*?'),?|,", s) if t is not None ]
>>> tokens
['1', '",2, "', '', '4', '', '', "',7, '", '8', '', '10', '']
如果要使用自定义分隔符，请用自己的分隔符替换正则表达式中每次出现的, 。
说明：
| = match alternatives e.g. ( |X) = space or X
.* = anything
x? = x or nothing
() = capture the content of a matched pattern
We have 3 alternatives:
1 "text" -> ".*?" -> due to escaping rules becomes - > \".*?\"
2 'text' -> '.*?'
3 delimiter -> ,
Since we want to capture the content of the text inside the quotes, we use ():
1 \"(.*?)\" (to keep the quotes use (\".*?\")
2 '(.*?)' (to keep the quotes use ('.*?')
Finally we don't want that split function reports an empty match if a
delimiter precedes and follows quotes, so we capture that possible
delimiter too:
1 ,?\"(.*?)\",?
2 ,?'(.*?)',?
Once we use the | operator to join the 3 possibilities we get this regexp:
r",?\"(.*?)\",?|,?'(.*?)',?|,"