How to replace all XHTML/HTML line breaks (<br>) with new lines?

Question

I am looking for the best br2nl function. I would like to replace all instances of <br> and <br /> with newlines \n. Much like the nl2br() function but the opposite.

I know there are several solutions in the PHP manual comments but I'm looking for feedback from the SO community on possible solutions.

Answer 1

I would generally say "don't use regex to work with HTML", but, on this one, I would probably go with a regex, considering that <br> tags generally look like either :

• <br>
• or <br/>, with any number of spaces before the /

I suppose something like this would do the trick :

$html = 'this <br>is<br/>some<br />text <br    />!'; $nl = preg_replace('#<br\s*/?>#i', "\n", $html); echo $nl; 

Couple of notes :

• starts with <br
• followed by any number of white characters : \s*
• optionnaly, a / : /?
• and, finally, a >
• and this using a case-insensitive match (#i), as <BR> would be valid in HTML