Python：搜索鍵，並在很大的Windows文件中用恆定值替換“，”之前的下一個單詞

Question

我最近才開始學習Python，並提出了需要您幫助的要求。 我有大型機背景，這是一個非常簡單的要求，可以使用DFSORT來完成，但是在python中，我搜索了論壇和Google，但找不到此問題的任何線索。

我有一個很大的Windows文件，它可以是3GB到5GB甚至更大。 我的要求是在每行中用一個關鍵字搜索該文件，如果找到該關鍵字，則用XXXXXXXXXX替換（結束）“，”之前的下一個單詞，關鍵字始終為“ name：”，要替換的值始終位於（ ，）之后的鍵。 可能並非所有的行都有鍵。 如果要替換的值為NULL，則必須從替換中忽略該值

樣本輸入文件：-

this is the name: roger,who won australian open
yes name: rafael nadal,who won french open
name: novak, is injured for this season
propably greatest of all time name: roger, had won wimbledon again.
this is the name: NULL,who will win US open !!!

輸出文件

this is the name: XXXXXXXXXX,who won australian open
yes name: XXXXXXXXXX,who won french open
name: XXXXXXXXXX, is injured for this season
propably greatest of all time name: XXXXXXXXXX, had won wimbledon again.
this is the name: NULL,who will win US open !!!

Answer 1

您可以使用正則表達式捕獲name: anysequenceofcharacters,字符串，並將其替換為name: XXXXXXXXXX, name: anysequenceofcharacters,

import re
with open('in', "rt") as fin:
with open('out', "wt") as fout:
    for line in fin:
        fout.write(re.sub('name:(?! NULL)([^,]+),', 'name: XXXXXXXXXX,', line))

Answer 2

無法發表評論，因此這是在@aoiee的基礎上建立的答案，該答案將遍歷文件：

with open('filename.txt', 'r') as f:
    lines = file.read()
    text = re.sub('name:(?! NULL)([^,]+),', 'name: XXXXXXXXXX,', lines)

with open('out.txt', 'w') as out:
    out.write(text)

Answer 3

除了aoiee的答案，您還可以閱讀並重寫文字，

如果數據很多，可能需要更長的時間

import fileinput
import re
with open('path to file.txt or whatever', 'r') as file :
  filedata = file.read()
new_data = re.sub('name:([^,]+),', 'name: XXXXXXXXXX,', filedata)
with open('path to file.txt or whatever', 'w') as file:
  file.write(new_data)

Answer 4

如果每一行都在換行符上，則可以執行以下操作而無需for循環：

def repel(mo):
    if mo.group(3) == 'NULL':
        return '{}{}{}{}'.format(mo.group(1), mo.group(2), mo.group(3), mo.group(4))
    return '{}{}{}{}'.format(mo.group(1), mo.group(2), 'XXXX,', mo.group(4))

pattern = re.compile('(.*)(name: )(\w+,)?(.*)')
re.sub(pattern, repel, _in, re.DOTALL)

基本上在每次比賽時都調用排斥功能，該功能將name:后的部分替換為XXXX 。