Collections Dart

Collections

List

final cityList = ['Paris', 'Londres', 'Rome'];
cityList.add('Amsterdam');
cityList.addAll(['Madrid', 'Barcelone']);
cityList.removeLast();
cityList.add('Rome');

final uppercaseCities = cityList
    .map((city) => city.toUpperCase())
    .toList();
print(uppercaseCities);

Documentation List

Set

Collection d’éléments uniques :

final citySet = {'Paris', 'Londres', 'Rome'};
citySet.add('Rome'); // N'ajoute pas de doublon
print('Cities $citySet');

Documentation Set

Map

final city = {
    'name': 'Paris',
    'country': 'France',
    'pictures': ['paris1.jpg', 'paris2.jpg'],
};

enum Status { pending, error, done }

Map<Status, Color> colorMap = {
    Status.pending: Colors.grey,
    Status.error: Colors.red,
    Status.done: Colors.green,
};

void main() {
    print(city['country']);
    print(colorMap[Status.error]);
}

Records

Depuis Dart 3.0 :

void main() {
    // Records positionnels
    final position = getPoint();
    print('position X : ${position.$1}, Y : ${position.$2}, Z : ${position.$3}');

    // Destructuring
    final (x, y, z) = getPoint();
    print('position X : $x, Y : $y, Z : $z');

    // Named records
    final coordinates = getPosition();
    print('longitude ${coordinates.longitude} latitude ${coordinates.latitude}');
}

(double, double, double) getPoint() {
    final x = computeX();
    final y = computeY();
    final z = computeZ();
    return (x, y, z);
}

({double longitude, double latitude}) getPosition() {
    final longitude = computeLongitude();
    final latitude = computeLatitude();
    return (latitude: latitude, longitude: longitude);
}