racket/collects/web-server/default-web-root/htdocs/lang-servlets/add03.ss
2008-02-24 21:27:36 +00:00

31 lines
1.1 KiB
Scheme

#lang web-server
(provide start)
;; get-number-from-user: string -> number
;; ask the user for a number
(define (gn msg)
(let ([req
(send/suspend/hidden
(lambda (ses-url k-hidden)
`(hmtl (head (title ,(format "Get ~a number" msg)))
(body
(form ([action ,(url->string ses-url)]
[method "post"]
[enctype "application/x-www-form-urlencoded"])
,(format "Enter the ~a number to add: " msg)
(input ([type "text"] [name "number"] [value ""]))
(input ([type "submit"]))
,k-hidden)))))])
(string->number
(bytes->string/utf-8
(binding:form-value
(bindings-assq #"number"
(request-bindings/raw req)))))))
(define (start initial-request)
`(html (head (title "Final Page"))
(body
(h1 "Final Page")
(p ,(format "The answer is ~a"
(+ (gn "first") (gn "second")))))))