Python正则表达式：如何在两个模式之间选择行

Question

考虑一个典型的实时聊天数据如下：

Peter (08:16): 
Hi 
What's up? 
;-D

Anji Juo (09:13): 
Hey, I'm using WhatsApp!

Peter (11:17):
Could you please tell me where is the feedback?

Anji Juo (19:13): 
I don't know where it is. 

Anji Juo (19:14): 
Do you by any chance know where I can catch a taxi ?
🙏🙏🙏

要将这个原始文本文件转换为数据帧，我需要编写一些正则表达式来标识列名，然后提取相应的值

请参阅https://regex101.com/r/X3ubqF/1

Index(time)     Name        Message
08:16           Peter       Hi 
                            What's up? 
                            ;-D
09:13           Anji Juo    Hey, I'm using WhatsApp!
11:17           Peter       Could you please tell me where is the feedback?
19:13           Anji Juo    I don't know where it is. 
19:14           Anji Juo    Do you by any chance know where I can catch a taxi ?
                            🙏🙏🙏

regexr"(?P<Name>.*?)\s*\((?P<Index>(?:\d|[01]\d|2[0-3]):[0-5]\d)\)"可以完美地提取时间和名称列的值，但我不知道如何为每个时间索引突出显示和提取来自特定发送者的消息

Answer 1

使用

(?m)^(?P<user>.*?)\s*\((?P<hhmm>(?:\d|[01]\d|2[0-3]):[0-5]\d)\):\s*(?P<Quote>.*(?:\n(?!\n).*)*)

见regex proof

Python code：

import re

s = "Peter (08:16): \nHi \nWhat's up? \n;-D\n\nAnji Juo (09:13): \nHey, I'm using WhatsApp!\n\nPeter (11:17):\nCould you please tell me where is the feedback?\n\nAnji Juo (19:13): \nI don't know where it is. \n\nAnji Juo (19:14): \nDo you by any chance know where I can catch a taxi ?\n🙏🙏🙏\n"

regex = r"^(?P<user>.*?)\s*\((?P<hhmm>(?:\d|[01]\d|2[0-3]):[0-5]\d)\):\s*(?P<Quote>.*(?:\n(?!\n).*)*)"

print(re.findall(regex, s, re.M))

结果：

[('Peter', '08:16', "Hi \nWhat's up? \n;-D"), ('Anji Juo', '09:13', "Hey, I'm using WhatsApp!"), ('Peter', '11:17', 'Could you please tell me where is the feedback?'), ('Anji Juo', '19:13', "I don't know where it is. "), ('Anji Juo', '19:14', 'Do you by any chance know where I can catch a taxi ?\n🙏🙏🙏\n')]

解释

                                        
  (?m)                     set flags for this block (with ^ and $
                           matching start and end of line) (case-
                           sensitive) (with . not matching \n)
                           (matching whitespace and # normally)
                                        
  ^                        the beginning of a "line"
                                        
  (?P<user>                   group and capture to "user" group:
                                        
    .*?                      any character except \n (0 or more times
                             (matching the least amount possible))
                                        
  )                        end of "user" group
                                        
  \s*                      whitespace (\n, \r, \t, \f, and " ") (0 or
                           more times (matching the most amount
                           possible))
                                        
  \(                       '('
                                        
  (hhmm                     group and capture to "hmm" group:
                                        
    (?:                      group, but do not capture:
                                        
      \d                       digits (0-9)
                                        
     |                        OR
                                        
      [01]                     any character of: '0', '1'
                                        
      \d                       digits (0-9)
                                        
     |                        OR
                                        
      2                        '2'
                                        
      [0-3]                    any character of: '0' to '3'
                                        
    )                        end of grouping
                                        
    :                        ':'
                                        
    [0-5]                    any character of: '0' to '5'
                                        
    \d                       digits (0-9)
                                        
  )                        end of "hhmm" group
                                        
  \)                       ')'
                                        
  :                        ':'
                                        
  \s*                      whitespace (\n, \r, \t, \f, and " ") (0 or
                           more times (matching the most amount
                           possible))
                                        
  (?P<Quote>                 group and capture to "Quote" group:
                                        
    .*                       any character except \n (0 or more times
                             (matching the most amount possible))
                                        
    (?:                      group, but do not capture (0 or more
                             times (matching the most amount
                             possible)):
                                        
      \n                       '\n' (newline)
                                        
      (?!                      look ahead to see if there is not:
                                        
        \n                       '\n' (newline)
                                        
      )                        end of look-ahead
                                        
      .*                       any character except \n (0 or more
                               times (matching the most amount
                               possible))
                                        
    )*                       end of grouping
                                        
  )                        end of "Quote" group

Answer 2

您可以使用re模块来解析字符串（regex101）：

import re

s = """
Peter (08:16): 
Hi 
What's up? 
;-D

Anji Juo (09:13): 
Hey, I'm using WhatsApp!

Peter (11:17):
Could you please tell me where is the feedback?

Anji Juo (19:13): 
I don't know where it is. 

Anji Juo (19:14): 
Do you by any chance know where I can catch a taxi ?
🙏🙏🙏
"""


all_data = []
for part in re.findall(
    r"^\s*(.*?)\s+\(([^)]+)\):\s*(.*?)(?:\n\n|\Z)", s, flags=re.M | re.S
):
    all_data.append(part)

df = pd.DataFrame(all_data, columns=["Index(time)", "Name", "Message"])
print(df)

印刷品：

  Index(time)   Name                                                      Message
0       Peter  08:16                                        Hi \nWhat's up? \n;-D
1    Anji Juo  09:13                                     Hey, I'm using WhatsApp!
2       Peter  11:17              Could you please tell me where is the feedback?
3    Anji Juo  19:13                                   I don't know where it is. 
4    Anji Juo  19:14  Do you by any chance know where I can catch a taxi ?\n🙏🙏🙏\n