Dart HMAC SHA 256 Example code

example.dart

import 'dart:html';
import 'dart:convert';
import 'package:crypto/crypto.dart';

void main() {

  String secret = 'secret';
  String message = 'Message';

  List<int> secretBytes = utf8.encode(secret);
  List<int> messageBytes = utf8.encode(message);
  
  var hMacSha256 = new Hmac(sha256, secretBytes);
  var hash = hMacSha256.convert(messageBytes);
  
  // output to html page
  querySelector('#hash').text = hash;
  // hash => qnR8UCqJggD55PohusaBNviGoOJ67HC6Btry4qXLVZc=
}