使用正则表达式过滤字符串后的值

Question

I have the following string s in python

ip access-list IpAclDscpTest
   10 permit ip any any dscp <value1>
   20 permit ip any any dscp <value2>
   30 permit ip any any dscp <value3>
   40 permit ip any any dscp <value4>
   50 permit ip any any dscp <value5

value<1-5> can be either numbers or string like 'abc31'

example

txt = '''ip access-list IpAclDscpTest
   10 permit ip any any dscp 0
   20 permit ip any any dscp af31
   30 permit ip any any dscp ef
   40 permit ip any any dscp 34
   50 permit ip any any dscp 46'''

Is there any way to filter out the values after dscp and put them in a list using regex?

Answer 1

Here's what I would do, it's a bit of a refinement on the other answers:

import re

txt = '''ip access-list IpAclDscpTest
   10 permit ip any any dscp 0
   20 permit ip any any dscp af31
   30 permit ip any any dscp ef
   40 permit ip any any dscp 34
   50 permit ip any any dscp 46'''

regex = r'''dscp\s+ # matches dscp and one or more spaces
            ([a-z0-9]+) # capture group, one or more lowercase alphanumerics
             \s*  # matches possible spaces after (0+)
              $ # this matches every endline (with MULTILINE flag below)
         '''

number_list = re.findall(regex, txt, re.MULTILINE | re.VERBOSE)

and number_list returns you:

['0', 'af31', 'ef', '34', '46']

Answer 2

试试这个新问题。

ouput = re.findall(r'dscp\s+(.*)\s+',s)

Answer 3

Make the front greedy

#!/usr/bin/python

input="""
ip access-list IpAclDscpTest
   10 permit ip any any dscp 0
   20 permit ip any any dscp 12
   30 permit ip any any dscp 18
   40 permit ip any any dscp 34
   50 permit ip any any dscp 46
"""

import re

for v in re.findall('.*dscp\s(\d+)', input):
    print v