regex - 正则表达式替换：替换文本，而不是代码

Question

我试图解决几天的正则表达式测验，但仍然无法正确解决。我已经很近了，但仍然无法通过。

任务：

在 HTML 页面中，将文本替换micro为µ. 哦，不要搞砸代码：不要更换内部<the tags>或&entities;

代替

• micro->µ
• abc micro->abc µ
• micromicro->µµ
• µmicro->µµ

不要触摸

• <tag micro />-><tag micro />
• µ->µ
• &abcmicro123;->&abcmicro123;

---

我试过这个，但最后失败了µ，我错过了什么？有人能指出我错过了什么吗？提前致谢！

我试过的：

正则表达式

((?:\G|\n)(?:.*?&.*?micro.*?;[\s\S]*?|.*?<.*?micro.*?>[\s\S]*?|.)*?)micro

替代

$1µ

标签： regexpcresubstitution

Answer 1

使用SKIP-FAIL 技术，但作为一个整体匹配：

(?:<[^<>]*>|&\w+;)(*SKIP)(*F)|\bmicro\b

见证明

解释

--------------------------------------------------------------------------------
  (?:                      group, but do not capture:
--------------------------------------------------------------------------------
    <                        '<'
--------------------------------------------------------------------------------
    [^<>]*                   any character except: '<', '>' (0 or
                             more times (matching the most amount
                             possible))
--------------------------------------------------------------------------------
    >                        '>'
--------------------------------------------------------------------------------
   |                        OR
--------------------------------------------------------------------------------
    &                        '&'
--------------------------------------------------------------------------------
    \w+                      word characters (a-z, A-Z, 0-9, _) (1 or
                             more times (matching the most amount
                             possible))
--------------------------------------------------------------------------------
    ;                        ';'
--------------------------------------------------------------------------------
  )                        end of grouping
--------------------------------------------------------------------------------
  (*SKIP)(*F)              Skip the match and go on matching from current location
--------------------------------------------------------------------------------
 |                        OR
--------------------------------------------------------------------------------
  \b                       the boundary between a word char (\w) and
                           something that is not a word char
--------------------------------------------------------------------------------
  micro                    'micro'
--------------------------------------------------------------------------------
  \b                       the boundary between a word char (\w) and
                           something that is not a word char