Text to URL

[Anon]

Here's the idea:

1. http://www.foo.org
   ==> <a href="http://www.foo.org" target="_blank">http://www.foo.org</a>
2. <a href="http://www.foo.org">http://www.foo.org</a>
   ==> <a href="http://www.foo.org" target="_blank">http://www.foo.org</a>
3. <a href="http://www.foo.org">foo</a>
   ==> <a href="http://www.foo.org" target="_blank">http://www.foo.org</a>
4. <a href="http://www.foo.org" target="blank">http://www.foo.org</a>
   ==> <a href="http://www.foo.org" target="blank">http://www.foo.org</a>

With regular expressions.

[Anon]

$txt = preg_replace("@(^{|\s)([:\s\"]+)://([\s]+)@","$1<a} href=\"$2://$3\" target=\"_blank\">$2://$3</a>",$txt);
$txt = preg_replace("@<a href=\"([^{:/\"\s])://([\"])\"([>])>([<])</a>@",} "<a href=\"$1://$2\" target=\"_blank\">$4</a>",$txt);