使用python和regex在字符串中查找關鍵字

Question

我想在字符串的開頭，結尾或字符串中的任何地方找到關鍵字。

我從這樣的事情開始：

import re
my_keyword = "in ocean"
regex = r'[^|\,\s]?in ocean\,\s|[^|\,\s]?in ocean$'

應該匹配：

in ocean there is big fish
in ocean
there is big fish in ocean
there is big fish in ocean but not in lakes
i like to swim in lake, in ocean too
in ocean, there is big fish

不應該匹配：

within ocean, you can find tresure
in oceania there is sirens
tintin ocean, the tresure hunter
do not dive within ocean

Answer 1

只需使用單詞邊界：

regex = r'\bin ocean\b'

單詞邊界在\\w字符和\\W字符之間，或\\w和^或$之間匹配。

regex101演示