jsonEncode

Learn to produce JSON with jsonEncode.

jsonEncode(obj) comes from dart:convert and turns a Dart object into JSON text. Map, List, String, num, bool, null are supported.

Example: var s = jsonEncode({'name': 'Ayşe', 'age': 30});. s is now the String {"name":"Ayşe","age":30}.

For your own classes, first convert to a Map with a toJson() method, then call jsonEncode. Passing a class directly throws.

String output format

jsonEncode output is single-line compact JSON: no spaces, keys double-quoted. {'a': 1} → {"a":1}.

For readable format use JsonEncoder.withIndent(' '): each key on a new line, indented. This is useful for debugging.

Special characters in String values are escaped: ' → \', newline → \n. This is done automatically.

Add import 'dart:convert';. Inside main add var s = jsonEncode({'name': 'Ayşe', 'age': 30});. Add print(s);.

Show example solution

import 'dart:convert';

void main() {
  var s = jsonEncode({'name': 'Ayşe', 'age': 30});
  print(s);
}

Encode an object to JSON

var s = ____(data);

Show answer

var s = jsonEncode(data);

Next lesson: fromJson