json - 从 JSON 文件中提取数据

Question

嘿，我正在尝试在此 JSON 文件中打印评论:

    # https://www.reddit.com/r/android/comments.json?limit=1

    require 'json'

    file = File.read('comments.json')
    data_hash=JSON.parse(file)
    comment = data_hash.fetch("body")
    print comment

当我运行它时它说找不到正文 key ？

Answer 1

require 'json'

file = File.read('comments.json')
data_hash=JSON.parse(file)
require 'pp'
pp data_hash

返回

{"kind"=>"Listing",
 "data"=>
  {"modhash"=>"",
   "children"=>
    [{"kind"=>"t1",
      "data"=>
       {"subreddit_id"=>"t5_2qlqh",
        "edited"=>false,
        "banned_by"=>nil,
        "removal_reason"=>nil,
        "link_id"=>"t3_5dq9i2",
        "link_author"=>"crazyg0od33",
        "likes"=>nil,
        "replies"=>"",
        "user_reports"=>[],
        "saved"=>false,
        "id"=>"da73zcw",
        "gilded"=>0,
        "archived"=>false,
        "report_reasons"=>nil,
        "author"=>"not_a_miscarriage",
        "parent_id"=>"t1_da73w7s",
        "score"=>1,
        "approved_by"=>nil,
        "over_18"=>false,
        "controversiality"=>0,
        "body"=>"Oh. The more you know",
        "link_title"=>
         "Get the Google Home speaker for $99 at Best Buy on Black Friday",
        "author_flair_css_class"=>nil,
        "downs"=>0,
        "body_html"=>
         "<div class=\"md\"><p>Oh. The more you know</p>\n</div>",
        "quarantine"=>false,
        "subreddit"=>"Android",
        "name"=>"t1_da73zcw",
        "score_hidden"=>true,
        "stickied"=>false,
        "created"=>1479604485.0,
        "author_flair_text"=>nil,
        "link_url"=>"http://blackfriday.bestbuy.com/?category=connected+home2",
        "created_utc"=>1479575685.0,
        "distinguished"=>nil,
        "mod_reports"=>[],
        "num_reports"=>nil,
        "ups"=>1}}],
   "after"=>"t1_da73zcw",
   "before"=>nil}}

所以你要找的 body 是:

data_hash["data"]["children"].first["data"]["body"]

有这么多哈希请求，你可能想写:

data_hash["data"]["children"].first["data"]["body"] rescue ""