php - Why would \n\r appear if I used nl2br()? -

someone made group on site has description \n\r. thing description text:

//convert urls links $group_description = preg_replace('#([\s|^])(www)#i', '$1http://$2', $group_description); $pattern = '#((http|https|ftp|telnet|news|gopher|file|wais):\/\/[^\s]+)#i'; $replacement = '<a href="$1" target="_blank">$1</a>'; $group_description = preg_replace($pattern, $replacement, $group_description);  $group_description = str_replace("\'" , "'", $group_description ); $group_description = nl2br($group_description);  /* convert e-mail matches appropriate html links */ $pattern = '#([0-9a-z]([-_.]?[0-9a-z])*@[0-9a-z]([-.]?[0-9a-z])*\\.'; $pattern .= '[a-wyz][a-z](fo|g|l|m|mes|o|op|pa|ro|seum|t|u|v|z)?)#i'; $replacement = '<a href="mailto:\\1">\\1</a>'; $group_description = preg_replace($pattern, $replacement, $group_description); 

you can see happening here.

you see says there \n\r welcome join.

why didn't become <br /> tag?

this important, here how put text db in first place:

$group_description = mysql_real_escape_string($_post['group_description']); // , insert $group_description db without doing more operations on it. 

any idea why still getting \n\r?

the problem \r , \n stored in database "\" "r" , "\" "\n" respectively. they're not stored carriage return or new line character slash character followed letter. when you're calling nl2br(), it's looking new line character, not textual representation of it. makes sense.

you use regular expression (preg_replace) or str_replace replace them. problem caused how data inserted in database.

for instance:

$string = str_replace('\n', "\n", $string); $string = str_replace('\r', "\r", $string); 

you'll notice used single quotes first 1 , double second. when using single quotes, "\r" , "\n" stored text, not special characters. why they're not stored in database.