textarea_json_fileから プロパティのキーと値の取出 (json3.html)

json data propaty取り出しは面倒なので、csv fileを扱うほうが楽。
JSONデータの読み込 JSONとは　　　　　　, JSONの作成とparse() / stringify()　　　　 Xml→Json 　 json→csv
json→csv変換　　 json→csv解説　　 csv→json変換

ファイル選択　 　　　 　　 　tag n2:　　　

ta --- ファイル選択 text data (no object)　........注意：json dataは " で囲まれていること。

json[1].name; ------Tom
json[1].favorite; ------- orange,ramen,programming 3個とも表示
alert(Object.keys(json));---0,1,2
alert(Object.keys(json[0]));---name,favorite

ta2 --- text data (no object) 　　


Object.keys(json[0]));// id, name,population,date_mod
json file

ta1
  const obj = [
    {name: 'Bob', favorite: ["apple", "curry", "video game"]},
    {name: 'Tom', favorite: ["orange", "ramen", "programming"]},
    {name: 'Jay', favorite: ["grape", "sushi", "shogi"]}
  ];//    " なしobject

  console.log(JSON.stringify(obj));// " 付く???
}

ta2
[
  {"id":"t0921", "name": "宇都宮", "population": 41295, "date_mod": "2003-8-12" },
  {"id":"t0922", "name": "小山", "population": 38756, "date_mod": "2003-5-15" },
  {"id":"t0923", "name": "佐野", "population": 71294, "date_mod": "2003-6-8" },
  {"id":"t0924", "name": "足利", "population": 27138, "date_mod": "2003-7-21" }
]


-----------------------
https://www.sejuku.net/blog/64361 ..... key の取得が [dim] ?????


----------------------
以下のobjectは、t0921 が id_name　になっている。----- ta2と異なる。
{
  "t0921": { "name": "宇都宮", "population": 41295, "date_mod": "2003-8-12" },
  "t0922": { "name": "小山", "population": 38756, "date_mod": "2003-5-15" },
  "t0923": { "name": "佐野", "population": 71294, "date_mod": "2003-6-8" },
  "t0924": { "name": "足利", "population": 27138, "date_mod": "2003-7-21" },
  "t0925": { "name": "日光", "population": 74682, "date_mod": "2003-4-19" },
  "t0926": { "name": "下野", "population": 82951, "date_mod": "2003-10-14" },
  "t0927": { "name": "さくら", "population": 96823, "date_mod": "2003-5-24" },
  "t0928": { "name": "矢板", "population": 57926, "date_mod": "2003-2-12" },
  "t0929": { "name": "真岡", "population": 64187, "date_mod": "2003-11-14" },
  "t0930": { "name": "栃木", "population": 82354, "date_mod": "2003-7-04" },
  "t0931": { "name": "大田原", "population": 72681, "date_mod": "2003-9-17" },
  "t0932": { "name": "鹿沼", "population": 23749, "date_mod": "2003-7-20" },
  "t0933": { "name": "那須塩原", "population": 12759, "date_mod": "2003-3-12" },
  "t0934": { "name": "那須烏山", "population": 62531, "date_mod": "2003-8-17" }
}
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https://qiita.com/ekzemplaro/items/df997054ba2ccc1a7add