(PHP 4, PHP 5, PHP 7)
nl2br — Inserts HTML line breaks before all newlines in a string
$string
[, bool $is_xhtml = true
] )
Returns string with '<br />' or
'<br>' inserted before all newlines (\r\n,
\n\r, \n and \r).
stringThe input string.
is_xhtmlWhether to use XHTML compatible line breaks or not.
Returns the altered string.
Example #1 Using nl2br()
<?php
echo nl2br("foo isn't\n bar");
?>
The above example will output:
foo isn't<br /> bar
Example #2 Generating valid HTML markup using the is_xhtml parameter
<?php
echo nl2br("Welcome\r\nThis is my HTML document", false);
?>
The above example will output:
Welcome<br> This is my HTML document
Example #3 Various newline separators
<?php
$string = "This\r\nis\n\ra\nstring\r";
echo nl2br($string);
?>
The above example will output:
This<br /> is<br /> a<br /> string<br />
| Version | Description |
|---|---|
| 5.3.0 |
Added the optional is_xhtml parameter. Before
this version '<br />' was always inserted.
|
It's important to remember that this function does NOT replace newlines with <br> tags. Rather, it inserts a <br> tag before each newline, but it still preserves the newlines themselves! This caused problems for me regarding a function I was writing -- I forgot the newlines were still being preserved.
If you don't want newlines, do:
<?php
$Result = str_replace( "\n", '<br />', $Text );
?>
Here's a more simple one:
<?php
/**
* Convert BR tags to nl
*
* @param string The string to convert
* @return string The converted string
*/
function br2nl($string)
{
return preg_replace('/\<br(\s*)?\/?\>/i', "\n", $string);
}
?>
Enjoy
to replace all linebreaks to <br />
the best solution (IMO) is:
<?php
function nl2br2($string) {
$string = str_replace(array("\r\n", "\r", "\n"), "<br />", $string);
return $string;
}
?>
because each OS have different ASCII chars for linebreak:
windows = \r\n
unix = \n
mac = \r
works perfect for me
Starting from PHP 4.3.10 and PHP 5.0.2, this should be the most correct way to replace <br /> and <br> tags with newlines and carriage returns.
<?php
/**
* Convert BR tags to newlines and carriage returns.
*
* @param string The string to convert
* @return string The converted string
*/
function br2nl ( $string )
{
return preg_replace('/\<br(\s*)?\/?\>/i', PHP_EOL, $string);
}
?>
(Please note this is a minor edit of this function: http://php.net/nl2br#86678 )
You might also want to be "platform specific", and therefore this function might be of some help:
<?php
/**
* Convert BR tags to newlines and carriage returns.
*
* @param string The string to convert
* @param string The string to use as line separator
* @return string The converted string
*/
function br2nl ( $string, $separator = PHP_EOL )
{
$separator = in_array($separator, array("\n", "\r", "\r\n", "\n\r", chr(30), chr(155), PHP_EOL)) ? $separator : PHP_EOL; // Checks if provided $separator is valid.
return preg_replace('/\<br(\s*)?\/?\>/i', $separator, $string);
}
?>
I test empirically this function nl2br and nl2br2 (create by ngkongs at gmail dot com).
Both work nice with different ASCII chars for linebreak, but the function nl2br2 is faster than nl2br.
nl2br2 ~ 0.0000309944153 s
nl2br ~ 0.0011141300201 s
The function nl2br2:
<?php
function nl2br2($string) {
$string = str_replace(array("\r\n", "\r", "\n"), "<br />", $string);
return $string;
}
?>
Seeing all these suggestions on a br2nl function, I can also see that neither would work with a sloppy written html line break.. Users can't be trusted to write good code, we know that, and mixing case isn't too uncommon.
I think this little snippet would do most tricks, both XHTML style and HTML, even mixed case like <Br> <bR /> and even <br > or <br />.
<?php
function br2nl($text)
{
return preg_replace('/<br\\s*?\/??>/i', '', $text);
}
?>
After a recent post at the forums on Dev Shed, I noticed that it isn't mentioned, so I will mention it.
nl2br returns pure HTML, so it should be after PHP anti-HTML functions ( such as strip_tags and htmlspecialchars ).
This is example with "\R" regex token which matches any unicode newline character.
"u" flag treate strings as UTF-16. Which is optional, depending on your use case.
<?php
public function nl2br($string)
{
return preg_replace('/\R/u', '<br/>', $string);
}
?>
NOTE:
preg_replace versions are much slower than using str_replace version or built-in nl2br.
Check out pcre.backtrack_limit php.ini setting for information about PCRE limit. It's good to know.
Some PHP7 benchmarks:
<?php
// nl2br()
function nl2br_str($string) {
return str_replace(["\r\n", "\r", "\n"], '<br/>', $string);
}
function nl2br_preg_R($string)
{
return preg_replace('/\R/u', '<br/>', $string);
}
function nl2br_preg_rnnr($string)
{
return preg_replace('/(\r\n|\n|\r)/', '<br/>', $string);
}
?>
# nl2br
## Time: 0.02895712852478 s
# nl2br_str
## Time: 0.027923107147217 s
# nl2br_preg_R
## Time: 0.13350105285645 s
# nl2br_preg_rnnr
## Time: 0.14213299751282 s
for bbcode :
<?php
$message = nl2br(preg_replace('#(\\]{1})(\\s?)\\n#Usi', ']', stripslashes($message)));
?>
This one works with br tags having attributes, in any case,
closed or not closed, and does not double linefeeds
<?php
/**
* convert br tags to nl
*
* @param string The string to convert
* @return string The converted string
*/
function br2nl($string)
{
return preg_replace("/<br[^>]*>\s*\r*\n*/is", "\n", $string);
}
?>
I combine this with strip_tags() for dead simple "contenteditable" fields allowing only text and linefeeds.
On the contrary, <b>mark at dreamjunky.comno-spam</b>, this function is rightfully named. Allow me to explain. Although it does re-add the line break, it does so in an attempt to stay standards-compliant with the W3C recommendations for code format.
According to said recommendations, a new line character must follow a line break tag. In this situation, the new line is not removed, but a break tag is added for proper browser display where a paragraph isn't necessary or wanted.
