title: Extract URL from string
body: <p>I'm trying to find a reliable solution to extract a url from a string of characters. I have a site where users answer questions and in the source box, where they enter their source of information, I allow them to enter a url. I want to extract that url and make it a hyperlink. Similar to how Yahoo Answers does it.</p>
  
  <p>Does anyone know a reliable solution that can do this?</p>
  
  <p>All the solutions I have found work for some URL's but not for others.</p>
  
  <p>Thanks</p>