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python - Python提取特定子字符串

问题描述

所以我在 Python 中有以下字符串：

teststr = "First Line.............................234" \
          "1.1.0 (L1) TestLine.........................567" \
          "1.1.1 (L1) Second Line.............................587"\
          "Third Line.............................856" \
          "1.1.2 (L2) Fourth Line.............................775"\
          "1.2.7 (L1) Fifth Line.............................262" \
          "1.5.3 (L1) Sixth Line .............................346"\
          "Seventh Line..............................234"

我只需要将（L1）中的信息保存在列表中。

我无法遍历行（如果行包含 L1 或其他内容），因为有时（L1）信息需要的信息超过在线（例如第二行第三行）。

我尝试了很多尝试再次拆分和加入字符串，但对我来说没有任何效果。

有谁知道我该怎么做？

标签： pythonstringlistsplit

解决方案

您可以在正则表达式上拆分字符串，然后遍历数据：

teststr = "First Line.............................234" \
          "1.1.0 (L1) TestLine.........................567" \
          "1.1.1 (L1) Second Line.............................587"\
          "Third Line.............................856" \
          "1.1.2 (L2) Fourth Line.............................775"\
          "1.2.7 (L1) Fifth Line.............................262" \
          "1.5.3 (L1) Sixth Line .............................346"\
          "Seventh Line..............................234"
import re
results = re.split(r'(\(L\d+\))',teststr)

这会将输入拆分为类似于(Ln)wheren可以是任何数字的任何值。

它给出了一个包含以下值的列表：

['First Line.............................2341.1.0 ',
 '(L1)',
 ' TestLine.........................5671.1.1 ',
 '(L1)',
 ' Second Line.............................587Third Line.............................8561.1.2 ',
 '(L2)',
 ' Fourth Line.............................7751.2.7 ',
 '(L1)',
 ' Fifth Line.............................2621.5.3 ',
 '(L1)',
 ' Sixth Line .............................346Seventh Line..............................234']

在这种情况下，我们只想选择 after 的值(L1)，所以我们在列表上循环（滑动）并仅在它之后打印值(L1)。

for x, y in zip(results, results[1:]):
  if x == '(L1)':
    print(y)

完整代码变为：

teststr = "First Line.............................234" \
          "1.1.0 (L1) TestLine.........................567" \
          "1.1.1 (L1) Second Line.............................587"\
          "Third Line.............................856" \
          "1.1.2 (L2) Fourth Line.............................775"\
          "1.2.7 (L1) Fifth Line.............................262" \
          "1.5.3 (L1) Sixth Line .............................346"\
          "Seventh Line..............................234"
import re
results = re.split(r'(\(L\d+\))',teststr)

for x, y in zip(results, results[1:]):
  if x == '(L1)':
    print(y)

这使：

 TestLine.........................5671.1.1 
 Second Line.............................587Third Line.............................8561.1.2 
 Fifth Line.............................2621.5.3 
 Sixth Line .............................346Seventh Line..............................234

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