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JsonObject which allows dot notation access to JSON.parse'd objects. Read the article on
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JsonObject for DART (

Version 1.0.19

Usage: Add to pubspec.yaml:

  json_object: any    

Now M7 (Dart Beta) compatible.

All tests passing with SDK

See Changelog.

You can use JsonObject in two different ways.

1 Accessing JSON Maps in a class-based fashion

Read the article about using this on the dartlang website:

JsonObject takes a json string representation, and uses the dart:json library to parse it back into a map. JsonObject then takes the parsed output, and converts any maps (recursively) into JsonObjects, which allow use of dot notation for property access (via noSuchMethod).


// create from existing JSON
var person = new JsonObject.fromJsonString('{"name":"Chris"}');
print(; = "Chris B";
person.namz = "Bob"; //throws an exception, as it wasn't in the original json
                     //good for catching typos

person.isExtendable = true;
person.namz = "Bob" //this is allowed now
String jsonString = JSON.encode(person); // convert back to JSON

It implements Map, so you can convert it back to Json using JSON.encode():

// starting from an empty map
var animal = new JsonObject();  
animal.legs = 4;  // equivalent to animal["legs"] = 4; = "Fido"; // equivalent to animal["name"] = "Fido";
String jsonString = JSON.encode(animal); // convert to JSON

Take a look at the unit tests to get an idea of how you can use it.

2. Experimental Using reflection to serialize from a real class instance to JSON

(Requires use of a the experimental mirrors branch)

Use objectToJson(myObj) to return a future containing the serialized string.

Example: import 'package:json_object/json_object.dart';

class Other {
    String name = "My Name";

class Basic {
   String myString = "foo";
   int myInt = 42;
   Other name = new Other();

main() {
  var basic = new Basic();
  objectToJson(basic).then((jsonStr) => print(jsonStr));


  • I still feel that there aren't enough tests - let me know if it works for you.

Many of the unit tests are based around specific questions from users, either here or on stack overflow.

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