Dart Quick Reference

void main() {
  print('Hello');
}

var name = 'Ada';

final created = DateTime.now();

const max = 100;

'$name is ${age + 1}'

int.parse('42')

int.tryParse(text)

42.toString()

String? nickname;

nickname ?? 'guest'

user?.name

nickname!

late final String token;

var nums = [3, 1, 2];

nums.add(4);

nums.map((n) => n * 2).toList()

nums.where((n) => n > 1)

nums.fold(0, (a, b) => a + b)

nums.sort();

users.sort((a, b) => a.age.compareTo(b.age));

nums.reversed.toList()

var ages = {'Ada': 36};
ages['Bob'] = 40;

[for (var n in nums) n * 2, if (showMore) 99]

[...a, ...b]

int add(int a, int b) => a + b;

void greet({required String name, int age = 0}) { }

class Dog {
  final String name;
  Dog(this.name);
  String bark() => 'Woof';
}

Dog.puppy() : name = 'Puppy';

class Puppy extends Dog { Puppy(super.name); }

class Robot with Walker { }

enum Status { active, disabled }

Future<String> load() async {
  final res = await http.get(Uri.parse(url));
  return res.body;
}

final results = await Future.wait([loadA(), loadB()]);

try {
  await load();
} catch (e) {
  print(e);
}

await for (final value in stream) {
  print(value);
}