Home >Backend Development >PHP Tutorial >How Can I Capture Newline Characters in PHP Using Regular Expressions?
PHP Regular Expression Puzzle: Capturing r and n with an Unexpected Escape Sequence
In the quest to capture newline characters in PHP, our intrepid developer encountered a roadblock when using v, only to discover its inadequacy against r and n. Determined to unveil an alternative solution, we embark on an exploration of PCRE's intricate world of newline escape sequences.
Enter R, an escape sequence that, when adorned with the Unicode modifier (u), awokens the ability to match any Unicode newline sequence, ranging from the familiar ASCII n and r to the exotic line separator (U 2028) and paragraph separator (U 2029).
<code class="php">preg_match('~\R~u', $string);</code>
For a more tailored approach, restricting R to only match carriage returns, linefeeds, or both can be achieved through:
<code class="php">preg_match('~(*BSR_ANYCRLF)\R~', $string);</code>
Remember, within character classes, R returns to its mundane state, becoming the literal character "R."
In conclusion, R provides a versatile mechanism for capturing newline characters, adapting to various Unicode conventions and specific matching requirements. May all your newline expeditions prove fruitful!
The above is the detailed content of How Can I Capture Newline Characters in PHP Using Regular Expressions?. For more information, please follow other related articles on the PHP Chinese website!