Python:使用正则表达式仅在字符串中的特定单词之后查找完整的文本

Question

有如下文本：

text = list of documents check 01 original invoice in favour of company z 02 cjpc abstract sheet weighment 
slip goods receipt note iz checklist creator id name 30009460 [e-mail]
checklist creation date 31 03 2018 checklist print date time 31 03 2018 10 45 57 note anything 
written manually on the checklist will not be considered invoice parth enterprise â invoice no dated 
kashish aarcade baroi road 18 25 mar 2018 village baroi delivery note mode terms of payment taluka 
mundra kutch supplierâ s ref other reference s gst no 24acypt3861 c1 z 7 dated buyer i buyer s order 
no 21 jun 2017 abc corporation 5700214006 â dated 40 mwp solar power plant i despatch document no 
vill bitta ta naliya abadasa despatched through destination march 18 terms of

目的：我想提取"发票"一词后面的文本，特别是"发票"的第二次出现

我的方法：

txt = re.findall('invoice (.*)',text)

在上面的方法中，我期待如下字符串列表：

txt = ['in favour of company z 02 cjpc abstract sheet weighment 
slip goods receipt note iz checklist creator id name 30009460 [e-mail]
checklist creation date 31 03 2018 checklist print date time 31 03 2018 10 45 57 note anything 
written manually on the checklist will not be considered','parth enterprise â invoice no dated 
kashish aarcade baroi road 18 25 mar 2018 village baroi delivery note mode terms of payment 
taluka ..... #rest of the string]

但是我得到了text中给出的整个字符串，即原始字符串。 如果我使用text.partition('invoice')则无法获得txt中所述的正确字符串。

任何帮助将不胜感激。

Answer 1

如果您想像问题中一样获得 2 场比赛，您可以使用 2 个捕获组。

第一次匹配，直到第一次出现发票。然后在第二次出现发票之前在组 1 中捕获。

然后再次匹配发票，并捕获组 2 中字符串的其余部分。

^.*? invoice (.*?) invoice (.*)

正则表达式演示 |蟒蛇演示

例如

import re
text = "list of documents check 01 original invoice in favour of company z 02 cjpc abstract sheet weighment slip goods receipt note iz checklist creator id name 30009460 [e-mail] creation date 31 03 2018 checklist print date time 31 03 2018 10 45 57 note anything written manually on the checklist will not be considered invoice parth enterprise â invoice no dated kashish aarcade baroi road 18 25 mar 2018 village baroi delivery note mode terms of payment taluka mundra kutch supplierâ s ref other reference s gst no 24acypt3861 c1 z 7 dated buyer i buyer s order no 21 jun 2017 abc corporation 5700214006 â dated 40 mwp solar power plant i despatch document no vill bitta ta naliya abadasa despatched through destination march 18 terms of"
regex = r"^.*? invoice (.*?) invoice (.*)"
matches = re.search(regex, text)
if matches:
print(matches.group(1))
print('n')
print(matches.group(2))

输出

in favour of company z 02 cjpc abstract sheet weighment slip goods receipt note iz checklist creator id name 30009460 [e-mail] creation date 31 03 2018 checklist print date time 31 03 2018 10 45 57 note anything written manually on the checklist will not be considered

parth enterprise â invoice no dated kashish aarcade baroi road 18 25 mar 2018 village baroi delivery note mode terms of payment taluka mundra kutch supplierâ s ref other reference s gst no 24acypt3861 c1 z 7 dated buyer i buyer s order no 21 jun 2017 abc corporation 5700214006 â dated 40 mwp solar power plant i despatch document no vill bitta ta naliya abadasa despatched through destination march 18 terms of

Answer 2

这可以通过split((方法轻松完成 例如：

myText="jhon is going abroad jhon is thinking about future jhon is absent"
1)  print(myText.split('jhon',1)[1])
output -> is going abroad jhon is thinking about future jhon is absent
2)  print(myText.split('jhon',2)[2])
output -> is thinking about future jhon is absent
3)  print(myText.split('jhon',3)[3])
output -> is absent
1 -> it will print text after first occurrence of jhon
2 -> it will print text after second occurrence of jhon
3 -> it will print text after third occurrence of jhon

Answer 3

您的正则表达式invoice (.*)将匹配第一个文字invoice后跟空格，然后(.*)贪婪地捕获组 1 中的其余文本，这是正在发生的事情，并且是预期的正确行为。

但是，如果您想获得您提到的输出，则必须相应地编写正则表达式。您可以使用以下正则表达式来实现所需的结果，

invoice (.*?)(?=(?:(?:invoice.*){2,}|$))

正则表达式解释：

• invoice- 匹配文字发票和空格
• (.*?)- 以懒惰的方式匹配文本
• (?=(?:(?:invoice.*){2,}|$))- 在看到 2 个文字invoice文本时立即停止匹配或在整个输入结束时停止匹配

演示

蟒蛇演示，

import re
s = '''list of documents check 01 original invoice in favour of company z 02 cjpc abstract sheet weighment slip goods receipt note iz checklist creator id name 30009460 [e-mail] creation date 31 03 2018 checklist print date time 31 03 2018 10 45 57 note anything written manually on the checklist will not be considered invoice parth enterprise â invoice no dated kashish aarcade baroi road 18 25 mar 2018 village baroi delivery note mode terms of payment taluka mundra kutch supplierâ s ref other reference s gst no 24acypt3861 c1 z 7 dated buyer i buyer s order no 21 jun 2017 abc corporation 5700214006 â dated 40 mwp solar power plant i despatch document no vill bitta ta naliya abadasa despatched through destination march 18 terms of'''
print(re.findall(r'invoice (.*?)(?=(?:(?:invoice.*){2,}|$))', s))

输出如你所愿，

['in favour of company z 02 cjpc abstract sheet weighment slip goods receipt note iz checklist creator id name 30009460 [e-mail] creation date 31 03 2018 checklist print date time 31 03 2018 10 45 57 note anything written manually on the checklist will not be considered ', 'parth enterprise â invoice no dated kashish aarcade baroi road 18 25 mar 2018 village baroi delivery note mode terms of payment taluka mundra kutch supplierâ s ref other reference s gst no 24acypt3861 c1 z 7 dated buyer i buyer s order no 21 jun 2017 abc corporation 5700214006 â dated 40 mwp solar power plant i despatch document no vill bitta ta naliya abadasa despatched through destination march 18 terms of']

Answer 4

更新：

我使用的正则表达式依赖于积极的回顾和积极的展望：

(?<=binvoice )(?:.*?)(?= invoiceb)

1. (?<=binvoice )仅当前面有以单词边界开头的invoice时，才与以下子表达式匹配。
2. (?:.*?)(?= invoiceb)零次或多次(非贪婪地(匹配任何字符，直到下一个字符invoice以单词边界结尾。

由于我复制了输入并包含原始输入中没有的换行符，因此我必须使用标志re.DOTALL以便.可以匹配换行符。但是，如果输入没有换行符(但不会造成伤害(，则不需要这样做。

查看正则表达式演示

代码：

import re
text= r"""list of documents check 01 original invoice in favour of company z 02 cjpc abstract sheet weighment
slip goods receipt note iz checklist creator id name 30009460 [e-mail]
checklist creation date 31 03 2018 checklist print date time 31 03 2018 10 45 57 note anything
written manually on the checklist will not be considered invoice parth enterprise â invoice no dated
kashish aarcade baroi road 18 25 mar 2018 village baroi delivery note mode terms of payment taluka
mundra kutch supplierâ s ref other reference s gst no 24acypt3861 c1 z 7 dated buyer i buyer s order
no 21 jun 2017 abc corporation 5700214006 â dated 40 mwp solar power plant i despatch document no
vill bitta ta naliya abadasa despatched through destination march 18 terms of"""
matches = re.findall(r'(?<=binvoice )(?:.*?)(?= invoiceb)', text, flags=re.DOTALL)
for i, match in enumerate(matches):
print(f'nMatch {i + 1}:n', match, sep='')

指纹：

Match 1:
in favour of company z 02 cjpc abstract sheet weighment
slip goods receipt note iz checklist creator id name 30009460 [e-mail]
checklist creation date 31 03 2018 checklist print date time 31 03 2018 10 45 57 note anything
written manually on the checklist will not be considered
Match 2:
parth enterprise â

Answer 5

使用用于拆分输入的更简单的正则表达式可以更有效地完成此问题：

import re
text= r"""list of documents check 01 original invoice in favour of company z 02 cjpc abstract sheet weighment
slip goods receipt note iz checklist creator id name 30009460 [e-mail]
checklist creation date 31 03 2018 checklist print date time 31 03 2018 10 45 57 note anything
written manually on the checklist will not be considered invoice parth enterprise â invoice no dated
kashish aarcade baroi road 18 25 mar 2018 village baroi delivery note mode terms of payment taluka
mundra kutch supplierâ s ref other reference s gst no 24acypt3861 c1 z 7 dated buyer i buyer s order
no 21 jun 2017 abc corporation 5700214006 â dated 40 mwp solar power plant i despatch document no
vill bitta ta naliya abadasa despatched through destination march 18 terms of"""
#matches = re.split(r'bs*invoices*b', text)[1:-1] # if arbitrary white space can come before and after "invoice"
matches = re.split(r'b ?invoice ?b', text)[1:-1]
for i, match in enumerate(matches):
print(f'nMatch {i + 1}:n', match, sep='')

指纹：

Match 1:
in favour of company z 02 cjpc abstract sheet weighment
slip goods receipt note iz checklist creator id name 30009460 [e-mail]
checklist creation date 31 03 2018 checklist print date time 31 03 2018 10 45 57 note anything
written manually on the checklist will not be considered
Match 2:
parth enterprise â