addEntries 方法

void addEntries(
  1. Iterable<MapEntry<K, V>> newEntries
)
override

将 newEntries 中的所有键/值对添加到该映射中。

如果 newEntries 中的键已经存在于该映射中，则相应的值将被覆盖。

操作相当于对可迭代中的每个 MapEntry 执行 this[entry.key] = entry.value。

final planets = <int, String>{1: 'Mercury', 2: 'Venus',
  3: 'Earth', 4: 'Mars'};
final gasGiants = <int, String>{5: 'Jupiter', 6: 'Saturn'};
final iceGiants = <int, String>{7: 'Uranus', 8: 'Neptune'};
planets.addEntries(gasGiants.entries);
planets.addEntries(iceGiants.entries);
print(planets);
// {1: Mercury, 2: Venus, 3: Earth, 4: Mars, 5: Jupiter, 6: Saturn,
//  7: Uranus, 8: Neptune}

实现

void addEntries(Iterable<MapEntry<K, V>> newEntries) {
  for (var entry in newEntries) {
    this[entry.key] = entry.value;
  }
}