Determine User Input Contains URL
<p>I have a input form field which collects mixed strings. </p>

<p><em><strong>Determine if a posted string contains an URL (e.g. <a href="http://link.com" rel="nofollow">http://link.com</a>, link.com, www.link.com, etc) so it can then be anchored properly as needed.</em></strong></p>

<p>An example of this would be something as micro blogging functionality where processing script will anchor anything with a link. Other sample could be this same post where 'http://link.com' got anchored automatically.</p>

<p>I believe I should approach this on display and not on input. How could I go about it?</p>
