0

I want to parse this JSON data but I have no idea how can I parse it.

{
    "kind": "Testing",
    "data": {
        "modhash": "fffffghhhhhhbf0bb4601d6158db548b5296632215a0",
        "dist": 75,
        "children": [
            {
                "kind": "z4",
                "data": {
                    "subreddit": "iOS",
                    "selftext": "I am iOS developer",
                    "author_fullname": "tyy_iif5q",
                    "saved": false,
                    "gilded": 0,
                    "clicked": false,
                    "title": "When is a good time to use docker?",
                    "subreddit_name_prefixed": "r/webdev",
                    "hidden": false,
                    "pwls": 6,
                    "downs": 0,
                    "hide_score": false,
                    "name": "t3_gwqan4",
                    "quarantine": false,
                    "link_flair_text_color": "dark",
                    "upvote_ratio": 0.96,
                    "subreddit_type": "public",
                    "ups": 277,
                    "total_awards_received": 0,
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                    "score": 277,
                    "author_premium": false,
                    "thumbnail": "self",
                    "edited": false,
                    "is_self": true,
                    "created": 1591333752,
                    "link_flair_type": "text",
                    "wls": 6,
                    "author_flair_type": "text",
                    "domain": "self.webdev",
                    "allow_live_comments": false,
                    "selftext_html": "<!-- SC_OFF --><div class=\"md\"><p>I just finished part 7 of the Full Stack Open course (<a href=\"https://www.fullstackopen.com/en\">www.fullstackopen.com/en</a>) and due to graphQL and typescript not being within the core content of the course, I thought I might try and learn docker. </p>\n\n<p>Turns out, trying to learn docker is just making me even more confused than when I didn't even know docker existed. </p>\n\n<p>​</p>\n\n<p>Could someone explain to me, when is a good time to use docker? How one would go about using docker, and when in someone's learning path would one ideally learn docker?</p>\n\n<p>​</p>\n\n<p>I am still learning react, databases, and overall front-end and back-end web development currently. The most I have done thus-far is hosting an app I made on heroku. I haven't setup a personal website, portfolio, or hosted an app on an independent website either.</p>\n</div><!-- SC_ON -->",
                    "archived": false,
                    "no_follow": false,
                    "is_crosspostable": true,
                    "pinned": false,
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                    "media_only": false,
                    "can_gild": true,
                    "spoiler": false,
                    "locked": false,
                    "visited": false,
                    "subreddit_id": "t5_2qs0q",
                    "id": "gwqan4",
                    "is_robot_indexable": true,
                    "author": "Sensualities",
                    "num_comments": 127,
                    "send_replies": true,
                    "whitelist_status": "all_ads",
                    "contest_mode": false,
                    "author_patreon_flair": false,
                    "permalink": "/r/webdev/comments/gwqan4/when_is_a_good_time_to_use_docker/",
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                    "url": "https://www.reddit.com/r/webdev/comments/gwqan4/when_is_a_good_time_to_use_docker/",
                    "subreddit_subscribers": 487697,
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            },
            {
                "kind": "t3",
                "data": {
                    "subreddit": "iOS",
                    "selftext": "I am iOS developer",
                    "author_fullname": "tyy_iif5q",
                    "saved": false,
                    "gilded": 0,
                    "clicked": false,
                    "title": "When is a good time to use docker?",
                    "subreddit_name_prefixed": "r/webdev",
                    "hidden": false,
                    "pwls": 6,
                    "downs": 0,
                    "hide_score": false,
                    "name": "t3_gwqan4",
                    "quarantine": false,
                    "link_flair_text_color": "dark",
                    "upvote_ratio": 0.96,
                    "subreddit_type": "public",
                    "ups": 277,
                    "total_awards_received": 0,
                    "is_original_content": false,
                    "is_reddit_media_domain": false,
                    "is_meta": false,
                    "can_mod_post": false,
                    "score": 277,
                    "author_premium": false,
                    "thumbnail": "self",
                    "edited": false,
                    "is_self": true,
                    "created": 1591333752,
                    "link_flair_type": "text",
                    "wls": 6,
                    "author_flair_type": "text",
                    "domain": "self.webdev",
                    "allow_live_comments": false,
                    "selftext_html": "<!-- SC_OFF --><div class=\"md\"><p>I just finished part 7 of the Full Stack Open course (<a href=\"https://www.fullstackopen.com/en\">www.fullstackopen.com/en</a>) and due to graphQL and typescript not being within the core content of the course, I thought I might try and learn docker. </p>\n\n<p>Turns out, trying to learn docker is just making me even more confused than when I didn't even know docker existed. </p>\n\n<p>​</p>\n\n<p>Could someone explain to me, when is a good time to use docker? How one would go about using docker, and when in someone's learning path would one ideally learn docker?</p>\n\n<p>​</p>\n\n<p>I am still learning react, databases, and overall front-end and back-end web development currently. The most I have done thus-far is hosting an app I made on heroku. I haven't setup a personal website, portfolio, or hosted an app on an independent website either.</p>\n</div><!-- SC_ON -->",
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                    "no_follow": false,
                    "is_crosspostable": true,
                    "pinned": false,
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                    "locked": false,
                    "visited": false,
                    "subreddit_id": "t5_2qs0q",
                    "id": "gwqan4",
                    "is_robot_indexable": true,
                    "author": "Sensualities",
                    "num_comments": 127,
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        ],
        "after": "ggggggg"
    }
}

I want to parse this JSON data but I have no idea how can I parse it.I worked with simple json but I have no idea how can I parse nested json please help me. I want to parse this JSON data but I have no idea how can I parse it.I worked with simple json but I have no idea how can I parse nested json please help me.

Imran
  • 11
  • Did you have a look at existing answers and resources before asking this question? – Sidak Jun 05 '20 at 12:45
  • For people to spend their time helping you on Stackoverflow, you're going to have to expend a bit more effort. Start by searching for "flutter json" If you still run into trouble, then come and update your question and say exactly where you are getting stuck. If you don't get stuck, maybe you can come and post an answer to your own question, so that next time someone struggles with this, they can find your solution. – dagelf Jun 05 '20 at 14:28
  • Does this answer your question? [Convert JSON into POJO (Object) similar to android in Flutter](https://stackoverflow.com/questions/51901760/convert-json-into-pojo-object-similar-to-android-in-flutter) – Charlie Armstrong Jun 05 '20 at 18:26

3 Answers3

0

Take a look at this library, it will help you ;)

https://pub.dev/packages/json_serializable

This lib will generate conversion code fromJson and toJson for each model annotated with @JsonSerializable

It take care of nested objects, type conversion and many other things ;)

Danaru
  • 274
  • 1
  • 6
0

Use this link to prepare model class of Json https://javiercbk.github.io/json_to_dart/

HttpResponse response = callApi;

then after getting response just use json.decode;

then use fromjson Method of your Model generated through link and your whole json is parsed 

Map userMap = jsonDecode(jsonString);
var user = User.fromJson(userMap);

User is Model created from site

rishabh mistry
  • 527
  • 3
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0

At first you need a classes representing JSON with the method fromJson which parses JSON into your object.

Also you should use nested classes for nested JSON fields

Alternatively, you could generate necessary classes with this class generator

class JSONRepresentation {
  final String kind;
  final Data data;
  JSONRepresentation({this.kind, this.data});
  JSONRepresentation .fromJson(Map<String, dynamic> data)
      : kind = data['kind'],
        data = Data .fromJson(data['data']);
}

class Data {
  final String modhash;
  final int dist;
  //final List<AnotherDataClass> children;
  final String after;

  Data({this.modhash, this.dist, this.after});
  Data .fromJson(Map<String, dynamic> data)
      : modhash = data['modhash'],
        dist = data['dist'],
        after = data['after'];
}

And then you can parse it using dart:convert and get data from objects representing JSON as below

import "dart:convert";

void main() {
  var jsonData = 
    '{"kind": "Testing",
      "data": { 
         "modhash": "fffffghhhhhhbf0bb4601d6158db548b5296632215a0",
         "dist": 75, 
         //"children": [...],
         "after": "ggggggg"}}';

  var parsedJson = json.decode(jsonData);
  var jsonRepresentationObject = JSONRepresentation.fromJson(parsedJson);

  //Example of getting data from objects  representing JSON
  print("kind: "+ jsonRepresentationObject.kind +
        "\nData modhash: " + jsonRepresentationObject.data.modhash);
}

You could test my example here - online dart compiler

Kelidon
  • 228
  • 1
  • 12