擅长:python、mysql、java
<p>Python不支持所有格量词或<code>\K</code></p>
<p>如果要替换匹配项,则不需要<code>\s?+</code></p>
<p>您可以使用<code>\s*</code>和<code>\K</code>,并使用<a href="https://pypi.org/project/regex/" rel="nofollow noreferrer">regex pypi module</a>和regex.sub</p>
<pre><code>\bUsername\s*[:;]\s*\K\S+
</code></pre>
<p><a href="https://regex101.com/r/MsCv1h/1" rel="nofollow noreferrer">Regex demo</a><a href="https://tio.run/##hc89C8IwEAbgPb/iuCnR4uLWIiKlkx@IH5MRSWnQDk1L7gr662OQFtx6y8vBM7xv9@FX65Yh1E3XegZvn/YtRGeYrXewAo9yXStdXin@prGaZrc0u8fQW32eoxBsiR/EPmKJI0srQxWZSjsU8HfYDwCySZHCFMlGgSp29rVj@RuwoL6Uw4YE8FQcd5u82BeHCyYw9lUqhC8" rel="nofollow noreferrer">Python demo</a></p>
<pre><code>import regex
pattern = r"(?i)\bUsername\s*[:;]\s*\K\S+"
test_str = ("Username:dasdsad\n"
"username ;dasdsad\n"
"username : dasdsad\n"
"username; dasdsad")
print(regex.sub(pattern, "REPLACEMENT", test_str))
</code></pre>
<p>输出</p>
<pre><code>Username:REPLACEMENT
username ;REPLACEMENT
username : REPLACEMENT
username; REPLACEMENT
</code></pre>