How to create JSONArray using string in flutter

How to create JSONArray using string in flutter like this :

String abc= "[{ "msg": "msg 1",  "asc": "asc 1" },......{ "message1": "msg 2", "asc": "asc 2"  }]";

If it's a small part of parsing than it's okay to manual parsing as per given above solution. I would recommend you use some tool to generate it for you.

https://plugins.jetbrains.com/plugin/12737-json-to-dart-class-jsontodartclass-

This IntelliJ plugin where you just paste your JSON and it will generate all the boilerplate code for you.

If you are not an IntelliJ user. You can use this website https://javiercbk.github.io/json_to_dart/

For advance try https://flutter.dev/docs/development/data-and-backend/json

Dart/Flutter, The Example will show about Flutter Json Array Parse Of Objects. This article will This article will creating a simple application using http Package. You can import 'dart:convert';List<User> modelUserFromJson(String str)� Start the watcher by running flutter pub run build_runner watch in the project root. It is safe to start the watcher once and leave it running in the background. Consuming json_serializable models. To decode a JSON string the json_serializable way, you do not have actually to make any changes to our previous code.

Best approach will be, Create a model.

class MyDataModel{
  String msg;
  String asc;

  MyDataModel({this.msg, this.asc});

  MyDataModel.fromJson(Map<String, dynamic> json) {
    msg = json['msg'];
    asc = json['asc'];
  }
}

Then import,

import 'dart:convert';

And finally you can make it,

String abc =
      '[{ "msg": "msg 1", "asc": "asc 1" },{ "msg": "msg 2", "asc": "asc 2" }]';

  @override
  Widget build(BuildContext context) {
    List<MyDataModel> dataList = parseJson(abc);

    return Scaffold(
      appBar: AppBar(),
      body: Text(dataList[1].msg),
    );
  }

  List<MyDataModel> parseJson(String str) {
    return List<MyDataModel>.from(
        json.decode(str).map((x) => MyDataModel.fromJson(x)));
  }

Flutter Json Array Parse Of Objects | by Ecco Suprastyo, In this article I'll teach you how to work with JSON in Dart and Flutter. First up, let's create a sample JSON string that we will use as a Here is a test to ensure we can decode a JSON array properly to a list of Students. Encoding a List of objects as a JSON Array. In this section we will take a list of Students and encode them as a JSON Array. This code is a litle more straight-forward then decoding. We use the map List.map method to represent the list of Students as a list of Map<String,String>. This becomes our JSON Array of students which we then assign to

String source = //json string array

List<T> fromJson(String source) => fromMap(json.decode(source));

static List<T> fromMap(Map<String, dynamic> map) {
  return map((m) => T( 
   msg:m['msg']
   asc:m['asc']));
}

Dart Fundamentals – Working with JSON in Dart and Flutter, Include a fromJson() factory method to make it easy to create a Photo starting with a JSON object. content_copy. class Photo { final int id; final String title; final� Flutter is an open-source mobile application development SDK created by Google. It is used to develop applications for Android and iOS. or you can visit https://flutter.dev. let's talk about JSON

Try following

class Data {
  final String msg;
  final String asc;

  const Data(this. msg, this. asc);
}


List<Data> parseData(String abc) {
  final parsed = json.decode(abc).cast<Map<String, dynamic>>();

  return parsed.map<Data>((json) => Data.fromJson(json)).toList();
}

It will return list of your jsonArray from String.

JSON and serialization, Dealing with a string can get complicated if you have a lot of data. Using Map values can make the code quite verbose. In this Dart/Flutter tutorial, we’re gonna look at ways to convert/parse JSON string into Object, Nested Object, how to parse JSON array, array of JSON objects into List. Finally, you can parse complex JSON into Nested Object (that also contains array as a field).

Parse JSON in the background, to add to that, does it also make sense to do a json.decode() . why not just pass the json string and let json_serializeable deal with it? Let’s go ahead and show a simple flutter project that highlights how to display array of strings from Json using FutureBuilder in Flutter. Create new Flutter Project In your Visual Studio Code, go to View menu > Command Palette. In the open dialog, select Flutter.

Parsing JSON in Flutter, Most mobile and web apps use JSON for tasks such as exchanging data with a web use the builder provided by this package, the Dart build system generates how Flutter apps can serialize and deserialize both with dart:convert and with� get JSON object from string using jsonDecode () function create class that has fields corresponding to key/value pairs of the JSON assign each JSON object value to the fields of the class instance (we will do this in factory.fromJson () method)

How do I deserialize a JSONArray? � Issue #135 � google , Dart, the language used by Flutter, comes with a good library to parse If you're unsure how to set up a Flutter app, check out Getting started with Now, let's add the code to output the JSON file to a String as well as the To access a JSON Array value, the same principle holds, ie we are using maps. get JSON string from JSON object/List using jsonEncode () function For every type of Object, Nested Object, simple List, List of Objects, or Nested Object containing List, we will implement toJson () method with some little difference. Dart/Flutter convert simple Object to JSON string Assume that we have a User class with fields: name & age.

Comments
  • Use ' or """ as the Dart string delimiters to avoid conflicting with the JSON string " delimiters. So, fx: String abc = '{"msg":"msg1"}';