Dart cheat sheat

Dart cheat sheat

自分用の備忘録

import

import 'dart:html';
import 'xxx:xxx'    as xxx;

entry point

main() {
  query('#status').text = 'Hi, Dart';
}

print log debug

num aNumber
print('The number is $aNumber.');
$variableName (or ${expression})

List

var list = [1,2,3];
assert(list.length == 3);
assert(list[1] == 2);

Map

var gifts = {                         // A map literal
// Keys       Values
  'first'  : 'partridge',
  'second' : 'turtledoves',
  'fifth'  : 'golden rings'
};

var map = new Map();                  // Use a map constructor.
map[1] = 'partridge';                 // Key is 1; value is 'partridge'.
map[2] = 'turtledoves';               // Key is 2; value is 'turtledoves'.
map[5] = 'golden rings';              // Key is 5; value is 'golden rings'.

A Quick Look at the Dart Language

import 'dart:math';

class Point {
  num x, y;
  Point(this.x, this.y);
  num distanceTo(Point other) {
    var dx = x - other.x;
    var dy = y - other.y;
    return sqrt(dx * dx + dy * dy);
  }
}

main() {
  var p = new Point(2, 3);
  var q = new Point(3, 4);
  print('distance from p to q = ${p.distanceTo(q)}');
}