c# - ProtoBuf 不反序列化具有接口(interface)的对象

Question

我有一个 TCP 套接字，我想使用 ProtoBuf 发送和接收对象。但我收到了这个错误:

Exception thrown: 'System.InvalidOperationException' in protobuf-net.dll

Type is not expected, and no contract can be inferred: Server.Packet.IMsg

我的界面:

 public interface IMsg { }

我要发送和接收的对象之一:

[ProtoContract]
public class PacketPerson : IMsg
{
    [ProtoMember(1)]
    public string Name{ get; set; }
    [ProtoMember(2)]
    public string Country { get; set; }
}

我的套接字在获得完整缓冲区后试图反序列化:

 IMsg msg = Serialization.Desirialize(SocketMemoryStream);

去理想化:

    public static IMsg Desirialize(MemoryStream ms) // socket buffer
    {
        ms.Position = 0;
        return Serializer.Deserialize<IMsg>(ms);
    }

Answer 1

yes, but I want to send multi-object and to identify them by using "Type type = packet.GetType();" Then use If statement "if (type == typeof(PacketPerson))"

我的建议(以作者身份):

[ProtoContract]
[ProtoInclude(1, typeof(PacketPerson))]
// future additional message types go here
class SomeMessageBase {}

[ProtoContract]
class PacketPerson : SomeMessageBase
{
    [ProtoMember(1)]
    public string Name{ get; set; }
    [ProtoMember(2)]
    public string Country { get; set; }
}

并反序列化/序列化 <SomeMessageBase> .库将在这里以正确的方式处理所有继承。在幕后，这将类似于(在 .proto 术语中)实现:

message SomeMessageBase {
    oneof ActualType {
        PacketPerson = 1;
        // ...
    }
}
message PacketPerson {
    string Name = 1;
    string Country = 2;
}

您现在可以使用多态性或类型测试来确定运行时的实际类型。新switch语法特别有用:

SomeMessageBase obj = WhateverDeserialize();
switch(obj)
{
    case PacketPerson pp:
        // do something person-specific with pp
        break;
    case ...:
        // etc
        break;
}