RequestHeaders is fired after connected user sends
request headers, but before any body content is sent - if
any will be sent at all. This place is convenient for
determining if user is about to upload files so you can
prepare yourself and setup Request.Filename
property to some exact location (otherwise, wodWebServer
will save received body to temporary location). If you plan
to support PUT methods of HTTP protocol, you might want to
use this event to point directly to location where file
will be saved.
But this is not it's only purpose. You have full
access to Request.Headers at
this point - and it tells you quite a bit about body
content that is about to arrive.
If you're expecting files to be uploaded, you can set Uploads.AutoParse
property in this event.