Question

I’m unable to serialize my class using protobuf-net, the issue seems to be that protobuf-net is unable to serialize the interface.

interface MyInterface
{
    string name;
}

[ProtoContract]
[ProtoInclude(1, typeof(MyClass1))]
[ProtoInclude(2, typeof(MyClass2))]
public abstract class ParentClass
{
    [ProtoMember(1)]
    List<MyInterface> elements;
}


[ProtoContract]
public class MyClass1 : ParentClass, MyInterface
{
    [ProtoMember(1)]
    int x;
}

[ProtoContract]
public class MyClass2 : MyInterface
{
    [ProtoMember(1)]
    string y;
}

I’m unable to serialize any object of type MyClass1, since the elements is a list of interface, which can be Mylass1 or MyClass2. I’m getting some encoding not set error.

Can anyone let me know how I can resolve this. Thanks.

Answer 1

In the current official versions I don’t include interface serialization support. However, I do have a patch contributed (from another user) that seems to enable this.

I haven’t applied this patch to the core yet, simply because I need to focus on finishing “v2” first before adding more features (especially as the feature would need to be completely re-implemented for v2), but I’m happy to share the patch with you if you would like.

Alternatively: use a base-class instead of an interface. That is supported (via [ProtoInclude]) – however, the fact that your MyClass1 already has a parent class complicates matters somewhat.

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Edit: this is now supported in v2. The code must know about the expected concrete implementations, obviously – but includes can now be attached to interfaces (or optionally specified in code for vanilla POCO models).