How to capitalize $2 in preg_replace? - tags

Question

I run a community site (built by hand using html, css, and php) for my wow guild. Recently, my members have demanded the ability to use tags like #username in their posts, which would then link to the users page. I already have this script, as listed below:
<?php
$string = '#user really?';
if (preg_match('/(^|\s)#([a-z0-9_]+)/i', $string))
{
$string = preg_replace('/(^|\s)#([a-z0-9_]+)/i', '#$2', $string);
echo $string;
}
else {
echo $string;
}
?>
This works fine, and I notice that the $2 is the user's name, but, since all user's names start with capital letters, the $2 needs to be capitalized, and not everyone does that. Is there a way to code it to automatically capitalize $2, or should I just tell users to remember to capitalize?
Thanx in advance,
Steven

Answer 1

use ucfirst ($2) to capitalize the first character
and strtoupper($2) if you want it all capital

Answer 2

I added more preg_replace and it now links to user no matter how u type name, as long as u have # symbol (#user, #USER, #User, #uSER, etc...). for anyone needing my solution, I will post it below:
<?php
$proper_str = "going to battle with #ADROK";
$proper_str = ucfirst(strtolower($proper_str));
$proper_str = preg_replace('/#[a-z]/e', 'ucfirst(strtoupper("$0"))', $proper_str);
$proper_str = preg_replace('/(^|\s)#([a-z0-9_]+)/i', ' #$2', $proper_str);
echo $proper_str;
?>
and if you change somethings around and make it:
<?php
$proper_str = "going to battle with e#mail.com";
if (preg_match('/(^|\s)#([a-z0-9_]+)/i', $proper_str))
{
$proper_str = ucfirst(strtolower($proper_str));
$proper_str = preg_replace('/#[a-z]/e', 'ucfirst(strtoupper("$0"))', $proper_str);
$proper_str = preg_replace('/(^|\s)#([a-z0-9_]+)/i', ' #$2', $proper_str);
echo $proper_str;
} else {
$proper_str = ucfirst("$proper_str");
echo $proper_str;
}
?>
Then it will leave email addresses alone and make sure first letter of post is capitalized!