https://www.v2ex.com/t/619370#;

py

#!/usr/bin/env python
# -*- coding: utf-8 -*-

# https://www.v2ex.com/t/619370#;

if __name__ == '__main__':
    # 我现在想通过 110.1.172.32 这个字符串 匹配到 object-group network 后面的 ShangHai 这个关键词, 请问正则怎么写? 感谢各位大佬
    text = """
 network-object host 109.17.49.131
object-group network KaGuan_12
 network-object host 109.17.26.11
 network-object host 109.17.26.12
object-group network ShangHai
 network-object host 110.1.60.91
 network-object host 110.1.60.92
 network-object host 110.1.172.31
 network-object host 110.1.172.32
 network-object host 110.238.250.57
 network-object host 110.238.250.58
object-group network wangguan_test
 network-object host 111.17.13.32
object-group network wangguan_app_2
 network-object host 111.17.9.54
 network-object host 111.17.9.63
"""

    group = 'object-group'
    ip = '110.1.172.32'

    text = text[:text.index(ip)]
    print "1 找到IP后，忽略后面的文本 \n", text

    text = text[text.rindex(group):]
    print "2 从后往前找 object-group， 并忽略前面的文本 \n", text

    text = text.splitlines()[0]
    print "3 取第一行内容 \n", text

    text = text[text.rindex(' ') + 1:]
    print "4 从后往前找空格，然后忽略空格前面的内容 \n", text

运行结果

1 找到IP后，忽略后面的文本 

 network-object host 109.17.49.131
object-group network KaGuan_12
 network-object host 109.17.26.11
 network-object host 109.17.26.12
object-group network ShangHai
 network-object host 110.1.60.91
 network-object host 110.1.60.92
 network-object host 110.1.172.31
 network-object host 

2 从后往前找 object-group， 并忽略前面的文本 

object-group network ShangHai
 network-object host 110.1.60.91
 network-object host 110.1.60.92
 network-object host 110.1.172.31
 network-object host 

3 取第一行内容 

object-group network ShangHai

4 从后往前找空格，然后忽略空格前面的内容 

ShangHai