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How to change the ProtoMember index for members in a type using Protobuf.net?

I have a type like this:

[ProtoContract] class Person { [ProtoMember(1)] public string Name {get;set:} [ProtoMember(2)] public int Id {get;set;} }

Later I realized that I needed another Age property, and added it like this:

 [ProtoContract] class Person { [ProtoMember(1)] public string Name {get;set:} [ProtoMember(3)] public int Age {get;set;} [ProtoMember(2)] public int Id {get;set;} }

But since I'm still under development, I want to change the Age ProtoMember from 3 to 2 and update Id ProtoMember .

Is there any way to make this easy? Or do I need to temporarily create another type in order to convert it back and forth until I can serialize it to the type I want in the updated form?

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I assume the problem is transferring old data? If so, then v2 can do it for you; however , I would also be personally turned on to say "meh, Age is # 3, Id remains # 2" (I do not see huge advantages when changing this number).

But as an example for a more general case:

 var oldModel = RuntimeTypeModel.Create(); // "false" here means "don't apply the normal rules; I'll tell you what to do" oldModel.Add(typeof(Person), false).Add("Name", "Id"); var newModel = RuntimeTypeModel.Create(); // "true" here means it will read from the attributes etc newModel.Add(typeof(Person), true); // now: load from an old file, and write to a new: var obj = oldModel.Deserialize(inFile, null, typeof(Person)); newModel.Serialize(outFile, obj);

Having 2 different instances of RuntimeTypeModel with different configurations, you can apply all kinds of odd transfers between data. But then again - using this just to make Age # 2 seem like a massive overkill. In fact, I would just make my class:

 [ProtoContract] class Person { [ProtoMember(1)] public string Name {get;set:} [ProtoMember(2)] public int Id {get;set;} [ProtoMember(3)] public int Age {get;set;} }

And look! They are magical in order!

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There is nothing in the library to help you with this. Therefore, you will need to write something to update the data if you really need to.

If you have a bunch of data, you probably just leave the field id as it is. It does not really matter. ID 1-16 I think that use only 1 byte as a field tag, higher numbers use more bytes.

The advantage of leaving the identifier as such is that it gives you forward and backward compatibility.

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