"is not registered in resolver" 使用 MessagePack 以抽象 class 序列化时出现异常

Question

正在尝试序列化 componentMappers 。异常抛出在 .Serialize():

var componentMappers = new Bag<ComponentMapper>();
var componentMappersS = MessagePackSerializer.Serialize(componentMappers);
var componentMappersD = MessagePackSerializer.Deserialize<Bag<ComponentMapper>>(componentMappersS);

FormatterNotRegisteredException: MonoGame.Extended.Entities.ComponentMapper is not registered in resolver: MessagePack.Resolvers.StandardResolver

[MessagePackObject]
    public abstract class ComponentMapper
    {
        [SerializationConstructor]
        protected ComponentMapper(int id, Type componentType)
        {
            Id = id;
            ComponentType = componentType;
        }

        [Key(0)]
        public int Id { get; set; }
        [Key(2)]
        public Type ComponentType { get; }
        public abstract bool Has(int entityId);
        public abstract void Delete(int entityId);
    }

    [MessagePackObject]
    public class ComponentMapper<T> : ComponentMapper
        where T : class
    {
        private readonly Action<int> _onCompositionChanged;
        
        // Custom
        [SerializationConstructor]
        public ComponentMapper(int id, Bag<T> components) : base(id, typeof(T))
        {
            Id = id;
            Components = components;
        }
    }
public class Bag<T> : IEnumerable<T>
    {
        [Key(0)]
        public T[] _items;
        [Key(1)]
        public bool _isPrimitive;

        [IgnoreMember]
        public int Capacity => _items.Length;
        [IgnoreMember]
        public bool IsEmpty => Count == 0;
        [IgnoreMember]
        public int Count { get; private set; }

        // Custom
        [SerializationConstructor]
        public Bag(T[] _items, bool _isPrimitive)
        {
            this._isPrimitive = _isPrimitive;
            this._items = _items;
        }
}

尽管如果针对特定类型进行序列化，即：

var componentMapper = new ComponentMapper<Human>(0, new Bag<Human>());
            var componentMapperS = MessagePackSerializer.Serialize(componentMapper);
            var componentMapperD = MessagePackSerializer.Deserialize<ComponentMapper<Human>>(componentMapperS);

没有问题。

Answer 1

发生这种情况是因为 ComponentMapper 是 abstract，所以我必须使用 MessagePacks Union。 MessagePack 尝试序列化抽象 class 但它不知道“在它下面”到底是什么类型，因此您必须用 Union.

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"is not registered in resolver" 使用 MessagePack 以抽象 class 序列化时出现异常

"is not registered in resolver" exception when serializing with abstract class using MessagePack

c#

serialization

msgpack