正则表达式-在多次出现的定界符之间匹配每个项目

Question

I would like to match the values between a given delimiter using a Regex expression in Python. I would like this to ignore surrounding white space. For example:

• The string 1, b cc, "a" and delimiter , will return three matches of 1 , b cc , "a"

• The string 4 + 5 + 2 +1 and delimiter + will return four matches of 4 , 5 , 2 , 1

Answer 1

import re
line = '1, b cc, "a"'
re.split(r'[;,]\s*', line)
Out[7]: ['1', 'b cc', '"a"']

line = '4 +   5 +   2  +1'
re.split(r'\s*[+]\s*', line)
Out[10]: ['4', '5', '2', '1']

The re.split() function is useful because you can specify multiple patterns for the separator.

In this case, for your first request, the separator is either a comma (,) , semicolon (;) , followed by any amount of extra whitespace . For your second request, the separator is plus (+) , surrounded by any amount of extra whitespaces .

Whenever that pattern is found, the entire match becomes the delimiter between whatever fields lie on either side of the match. The result is a list of fields, just as with str.split()

Answer 2

You can do this with the re.split() method.

import re

re.split('\s*,\s*', '1, b cc, "a"')

re.split('\s*\+\s*', '4 +   5 +   2  +1')