What do you mean by cancel it? Forcibly terminate the TCP/IP connection?
Immediately say “I don’t want you here�
Your quickest bet would be to set Response.StatusCode to an HTTP code of
your liking, relating to the cancellation.
I’d look into the 4xx or 5xx family of error codes, codes such as:
400 Bad Request
401 Unauthorized
403 Forbidden
404 Not Found
406 Not Acceptable
503 Service Unavailable
Brendan