Often when I look through the PHP manual for certian functions, I see things like this:

PHP Code:

 <?php
// get host name from URL
preg_match('@^(?:http://)?([^/]+)@i',
    "http://www.php.net/index.html", $matches);
$host = $matches[1];

// get last two segments of host name
preg_match('/[^.]+\.[^.]+$/', $host, $matches);
echo "domain name is: {$matches[0]}\n";
?>

I know what it does, and have used it, but one thing I dont understand is this: /[^.]+\.[^.]+$/ or @^(?:http://)?([^/]+)@i (from the example above. ONly part I really understand of those is that the i means case insensitive.

Iv looked through the manual but cant seem to find anything

http://regexlib.com/CheatSheet.aspx

This will tell you what each character means so you can start to decipher the above regex.

The second one means "many not-a-dots, then dot, then again many not-a-dots at the end of the line". The first one is too complicated for me though I understand what it does. But I would do the same thing in another way.

thanks guys, been helpful.

Im trying to modify the code i showed in my OP so that it grabs the entire url, not just the host/http. So far, no dice. Any help?

What entry data do you have and what do you want to obtain from it?

http://www.regular-expressions.info/

Originally Posted by mtishetsky

What entry data do you have and what do you want to obtain from it?

Say somebody posts a URL in their comment, I want to be able to grab that url and turn it into a link.