问题
I'm doing a project where I'm parsing JSON from the Riot Games API, and I'm having trouble. I'm pretty new to this, so bear with me:
The API returns JSON, for example:
{"forcinit":{"id":35979437,"name":"F O R C I N it","profileIconId":576,"summonerLevel":30,"revisionDate":1427753158000}}
in my code, I have the following:
#lang racket
(require 
 racket/gui/base
 net/url
 json
 racket/format
)
; --- Query API
(define api-request "https://na.api.pvp.net/api/lol/na/v1.4/summoner/by-name/SUMMONER_NAME?api_key=8864143b-a987-45a8-b49d-53c0a7677100")
(define (query-for-summoner name)
  (define summoner-request (string->url (string-replace api-request "SUMMONER_NAME" name)))
  ; Define request parameters, setup for output
  (define sh (get-pure-port summoner-request #:redirections 5))
  (define summoner-hash-str (port->string sh))
  (define summoner-hash-json (string->jsexpr summoner-hash-str))
  (define summoner (hash-ref summoner-hash-json name))
  ;I can't figure out how to make it so the "name" in the above line gets evaluted to the input, but read in as a literal 
  ;in order for it to correctly be identified for the hash. as of now, for example if i type in "Dyrus" in the gui box
  ; it says
  ;hash-ref: no value found for key
  ;key: "Dyrus"
  ;yet if i replace name with 'dyrus it works correctly.
  ;If you know of a way to take a variable and have racket read it as a literal, I would love to hear it.
  ;I've tried serching the documentation and googling but I can't seem to find what I'm looking for.
  (define summoner-id    (hash-ref summoner 'id))
  (define summoner-name  (hash-ref summoner 'name))
  (define summoner-icon  (hash-ref summoner 'profileIconId))
  (define summoner-level (hash-ref summoner 'summonerLevel))
  (printf "Results for: ~a\n" summoner-name)
  (printf "- ID: ~a\n" summoner-id)
  (printf "- Icon ID: ~a\n" summoner-icon)
  (printf "- Level: ~a\n" summoner-level)
)
; --- Build Frame
(define frame (new frame% 
 [label "League of Legends Statistics Tracker"]
 [width 300]
 [height 300]))
(send frame show #t)
(define msg (new message% 
 [parent frame]
 [label "Welcome to the LoL Stats Tracker."]))
(define sn-input (new text-field% 
 [parent frame]
 [label "Summoner Name: "]
 [init-value "omithegreat"]
 [callback (lambda(f ev)
             (send f get-value))
             ]))
(define submit-button (new button% 
 [parent frame]
 [label "Search"]
 [callback (lambda (button event)
             (let ([v (send sn-input get-value)])
               (query-for-summoner v))
             (send msg set-label "Searching for user..."))]))
I edited out my riot API private key; The code works fine when I replace name with whatever name I put in the gui box, for example if I searched for dyrus, and i replace "(define summoner (hash-ref summoner-hash-json name))" with (define summoner (hash-ref summoner-hash-json 'dyrus))
it works fine. Is there a way so I can input the name, then turn the name string into a literal, like the same string with a ' infront?
回答1:
Okay, I think Dan D. should simply have posted his comment as an answer:
I (also) think you're looking for
string->symbol
(If you upvote this, you should also upvote Dan D.'s comment, above....)
来源:https://stackoverflow.com/questions/29360497/racket-string-to-literal