containsValue method Null safety

bool containsValue(
  1. Object? value
)
override

Whether this map contains the given value.

Returns true if any of the values in the map are equal to value according to the == operator.

final moonCount = <String, int>{'Mercury': 0, 'Venus': 0, 'Earth': 1,
  'Mars': 2, 'Jupiter': 79, 'Saturn': 82, 'Uranus': 27, 'Neptune': 14 };
final moons3 = moonCount.containsValue(3); // false
final moons82 = moonCount.containsValue(82); // true

Implementation

bool containsValue(Object? value) {
  for (K key in keys) {
    if (this[key] == value) return true;
  }
  return false;
}