title: How can I get my webapp's base URL in ASP.NET MVC?
body: <p>How can I quickly determine what the root URL is for my ASP.NET MVC application?  I.e., if IIS is set to serve my application at <a href="http://example.com/foo/bar" rel="noreferrer">http://example.com/foo/bar</a>, then I'd like to be able to get that URL in a reliable way that doesn't involve getting the current URL from the request and chopping it up in some fragile way that breaks if I re-route my action.</p>
  
  <p>The reason that I need the base URL is that this web application calls another one that needs the root to the caller web application for callback purposes.</p>