title: ASP.NET - in Global.asax detect ASPX page request vs. other things
body: <p>I have an ASP.NET application where I want to set some additional HTTP headers (related to page expiration) if the request is for a normal ASPX page.  However, I don't want to add these headers for things like images, or AXD handlers, or static HTML pages, etc.</p>
  
  <p>What is the best way to detect, inside Global.asax request begin handler, that the current request is for an ASP.NET page?</p>
  
  <p>It seems wrong to me to look at the URL for "aspx" because then when they request root pages (such as myapp.com/ or myapp.com/products) it won't work.  And it just seems fragile.</p>
  
  <p>Thanks,</p>
  
  <p>~ Justin</p>