title: How do I turn a relative URL into a full URL?
body: <p>This is probably explained more easily with an example. I'm trying to find a way of turning a relative URL, e.g. "/Foo.aspx" or "~/Foo.aspx" into a full URL, e.g. <a href="http://localhost/Foo.aspx" rel="noreferrer">http://localhost/Foo.aspx</a>. That way when I deploy to test or stage, where the domain under which the site runs is different, I will get <a href="http://test/Foo.aspx" rel="noreferrer">http://test/Foo.aspx</a> and <a href="http://stage/Foo.aspx" rel="noreferrer">http://stage/Foo.aspx</a>.</p>
  
  <p>Any ideas?</p>