PHP preg_replace replacing newlines, but nothing works

I have a text field retrieved by a Solr query that contains the body of an email. I am trying to replace embedded line breaks with paragraph tags via PHP like so:

$text = $item->Body[0];
$new_line = array("rn", "n", "r");
preg_replace($new_line, '</p><p>', $text);
echo $text;

When I show the result in my IDE/debugger the newline characters are not replaced and are still there:

I have been going through threads on this site trying patterns suggested by different people including “/s+/” and PHP_EOL and “/(rn|r|n)/” and nothing works. What am I doing wrong?

Answer

You are missing the delimiter around your regex strings and you are not assigning the value.
You can also reduce your regex:

$text = preg_replace("/r?n|r/", '</p><p>', $text);

You might want switch to the multibyte safe version. They work with Unicode and you don’t need delimiters there 😉

$text = mb_ereg_replace("r?n|r", '</p><p>', $text);