MapField<TKey, TValue>
public sealed class MapField<TKey, TValue> : IDeepCloneable<MapField<TKey, TValue>>, IDictionary<TKey, TValue>, ICollection<KeyValuePair<TKey, TValue>>, IEnumerable<KeyValuePair<TKey, TValue>>, IEnumerable, IEquatable<MapField<TKey, TValue>>, IDictionary, ICollection, IReadOnlyDictionary<TKey, TValue>, IReadOnlyCollection<KeyValuePair<TKey, TValue>>
public MapField()