Question

我有各种数据类型的对象列表（DateTime，int，decimal，string）。

List<object> myObjects = new List<object>();
myObjects.Add(3);
myObjects.Add(3.9m);
myObjects.Add(DateTime.Now);
myObjects.Add("HELLO");

我能够使用protobuf-net序列化此列表，但反序列化总是抛出异常：＆＃34;附加信息：不期望类型，也不能推断出合同：System.Object＆＃34;。

using (var ms = new MemoryStream())
{
    Serializer.Serialize(ms, list2);
    var bytes = ms.ToArray();
    ms.Position = 0;
    var clone = Serializer.Deserialize(typeof(List<object>), ms); //Throws exception
}

我没有任何明确的合同，我想这是问题所在？但是，我确实知道序列化对象的预期类型是什么，但我如何告诉protobuf-net？

Answer 1

检查这些以了解为什么这是一种方法：

The need for a parameterless constructor
why dynamic instead of object wouldn't have worked
为什么DynamicType=true wouldn't have worked
the need for an abstract base class and concrete implementations，由protobuf-net的创建者
why no serializer for object

抽象基础

    [ProtoContract]
    [ProtoInclude (1, typeof(ObjectWrapper<int>))]
    [ProtoInclude(2, typeof(ObjectWrapper<decimal>))]
    [ProtoInclude(3, typeof(ObjectWrapper<DateTime>))]
    [ProtoInclude(4, typeof(ObjectWrapper<string>))]
    abstract class ObjectWrapper {
        protected ObjectWrapper() {}
        abstract public object ObjectValue { get; set; }
    }

实施

    [ProtoContract()]
    class ObjectWrapper<T> : ObjectWrapper
    {
        public ObjectWrapper(): base() { }
        public ObjectWrapper(T t) { this.Value = t; }

        [ProtoIgnore()]
        public override object ObjectValue
        {
            get { return Value; }
            set { Value = (T)value; }
        }

        [ProtoMember(1)]
        public T Value { get; set; }
    }

测试

        var myObjects = new List<ObjectWrapper>();
        myObjects.Add(new ObjectWrapper<int>(3));
        myObjects.Add(new ObjectWrapper<decimal>(3.9m));
        myObjects.Add(new ObjectWrapper<DateTime> (DateTime.Now));
        myObjects.Add(new ObjectWrapper<string> ("HELLO"));
        var clone = Serializer.DeepClone(myObjects);

是否可以使用协议缓冲区序列化System.Object对象列表

1 个答案: