Question

i’m not sure this problem whether is the bug or it’s just this,before i can’t noticed this.

i create a Document class and declare the protobuf-net restrict.

[ProtoContract]
public class Document
{
    [ProtoMember(1)]
    private Dictionary<string,string> _items;

    [ProtoMember(2)]
    public int DocNumber
    {
        get;
        set;
    }

    public Document()
    {
        this.DocNumber = -1;
        this._items = new Dictionary<string,string>();    
    }

    public byte[] Serialize()
    {
        byte[] bytes = null;
        using (var ms = new MemoryStream())
        {
            Serializer.Serialize(ms, this);
            bytes = ms.ToArray();
            ms.Close();
        }
        return bytes;           
    }

    public static Document Deserialize(byte[] bytes)
    {
        Document obj = null;
        using (var ms = new MemoryStream(bytes))
        {
            obj = Serializer.Deserialize<Document>(ms);
            ms.Close();
        }
        return obj;
    }
 }

in the test code:

  var doc = new Document();
  doc.DocNumber = 0;          
  var bytes = doc.Serialize();
  var new_doc = Document.Deserialize(bytes);
  Console.WriteLine(new_doc.DocNumber + " vs " + doc.DocNumber);

the output message is : -1 vs 0.i can’t believe this result(the correct result is 0 vs 0),so i change the doc.DocNumber = 0 to doc.DocNumber = 1,
the output is correct: 1 vs 1.

this problem means i can’t assign the zero to the DocNumber property,in the constructure method of the Document i must be declare the DocNumber property is -1.

someone can help me? this problem is my cause or the protobuf-net cause? thanks.

Answer 1

By default. It assumes zero values as defaults. I regret this design choice, so it can be disabled in v2, but is preserved for compatibility. You can, in both v1 and v2, also simply tell it that -1 is the default:

[ProtoMember(2), DefaultValue(-1)]
public int DocNumber