php - 匹配字符集和可选实体

Question

所以我想使用这段代码在字符串的每 5 个字符中插入一个分词符。

([^\s-]{5})([^\s-]{5})

不幸的是，它也会在实体字符 (&#xxx;) 上中断。有人能给我一个不会破坏实体代码的例子吗？我要断开的字符串来自 xml，因此实际实体被进一步转义 (&#xxx;)。

编辑代码示例

preg_replace('/([^\s-]{5})([^\s-]{5})/', '$1­$2', $subject)

Given the word "Fårevejle"
Expect "Få­revejle" as result
But it outputs "F­5;revejle" instead

Answer 1

假设你想在五个字符之后拆分每个单词，除非它们已经被连字符分隔，将一个实体视为单个字符，试试这个:

$result = preg_replace(
    '/            # Start the match 
    (?:           # at one of the following positions:
     (?<=         # Either right after...
      [\s-]       # a space or dash
     )            # end of lookbehind
     |            # or...
     \G           # wherever the last match ended.
    )             # End of start condition.
    (             # Now match and capture the following:
     (?>          # Match the following in an atomic group:
      &amp;\#\w+; # an entity
      |           # or
      [^\s-]      # a non-space, non-dash character
     ){5}         # exactly 5 times.
    )             # End of capture
    (?=[^\s-])    # Assert that we\'re not at the end of a "word"/x', 
    '\1&shy;', $subject);

这改变了

supercalifragilisticexpidon'tremember! 
alrea-dy se-parated 
count entity as one characterřblahblah
Fårevejle

进入

super­calif­ragil­istic­expid­on'tr­ememb­er! 
alrea-dy se-parat­ed 
count entit­y as one chara­cterř­blahb­lah
Fårev­ejle