containsKey method
Whether this map contains the given key
.
Returns true if any of the keys in the map are equal to key
according to the equality used by the map.
final moonCount = <String, int>{'Mercury': 0, 'Venus': 0, 'Earth': 1,
'Mars': 2, 'Jupiter': 79, 'Saturn': 82, 'Uranus': 27, 'Neptune': 14};
final containsUranus = moonCount.containsKey('Uranus'); // true
final containsPluto = moonCount.containsKey('Pluto'); // false
Implementation
@override
bool containsKey(Object? key) => _entries.containsKey(key);