C#: The input stream is not a valid binary format

Question

I have a problem with deserializing in C#/ASP.NET, which gives the exact error:

The input stream is not a valid binary format. The starting contents (in bytes) are: 41-41-45-41-41-41-44-2F-2F-2F-2F-2F-41-51-41-41-41 ...

What I am trying to do

I have a structure with 3 classes. I have a class A which is a base class, and then class B and C which are derived from A.

I am trying to store random types of B and C in the database using LINQ to SQL, in a column with the type VARCHAR(MAX). I cannot use BINARY as the length is around 15.000.

My code...

Error is in the LAST codeblock

C# Code in Business layer- Storing a record

    private void AddTraceToDatabase(FightTrace trace)
    {
        MemoryStream recieverStream = new MemoryStream();
        MemoryStream firedStream = new MemoryStream();
        MemoryStream moveStream = new MemoryStream();

        BinaryFormatter binaryFormatter = new BinaryFormatter();
        binaryFormatter.Serialize(recieverStream,trace.Reciever);
        binaryFormatter.Serialize(firedStream,trace.FiredBy);
        binaryFormatter.Serialize(moveStream,trace.Move);

        string reciever = Convert.ToBase64String(recieverStream.ToArray());
        string fired = Convert.ToBase64String(firedStream.ToArray());
        string move = Convert.ToBase64String(moveStream.ToArray());


        this.dataAccess.AddFightTrace(trace.TraceType.ToString(),reciever,move,fired,trace.DateTime,this.FightId);
    }

C# Code in Data access layer - Storing a record

    public void AddFightTrace(string type, string reciever, string Move, string firedBy, DateTime firedAt, int fightid)
    {
        GameDataContext db = new GameDataContext();
        dbFightTrace trace = new dbFightTrace();
        trace.TraceType = type;

        trace.Reciever = reciever;
        trace.Move = Move;
        trace.FiredBy = firedBy;
        trace.FiredAt = firedAt;
        trace.FightId = fightid;

        db.dbFightTraces.InsertOnSubmit(trace);
        db.SubmitChanges();
    }

C# Code getting the entry in the database

    public List<dbFightTrace> GetNewTraces(int fightid, DateTime lastUpdate)
    {
        GameDataContext db = new GameDataContext();
        var data = from d in db.dbFightTraces
                   where d.FightId==fightid && d.FiredAt > lastUpdate
                   select d;

        return data.ToList();
    }

C# Factory, converting from LINQ to SQL class to my objects

THIS IS HERE THE ERROR COMES

    public FightTrace CreateTrace(dbFightTrace trace)
    {
        TraceType traceType = (TraceType) Enum.Parse(typeof(TraceType), trace.TraceType);
        BinaryFormatter formatter = new BinaryFormatter();

        System.Text.UTF8Encoding enc = new System.Text.UTF8Encoding();

        MemoryStream recieverStream = new MemoryStream(enc.GetBytes(trace.Reciever));
        recieverStream.Position = 0;
        MemoryStream firedStream = new MemoryStream(enc.GetBytes(trace.FiredBy));
        firedStream.Position = 0;
        MemoryStream movedStream = new MemoryStream(enc.GetBytes(trace.Move));
        movedStream.Position = 0;

        // THE NEXT LINE HERE CAUSES THE ERROR
        NPC reciever = formatter.Deserialize(recieverStream) as NPC;
        Player fired = formatter.Deserialize(firedStream) as Player;
        BaseAttack attack = formatter.Deserialize(movedStream) as BaseAttack;

        FightTrace t = new FightTrace(traceType,reciever,attack,fired);
        t.TraceId = trace.FightTraceId;
        t.DateTime = trace.FiredAt;
        return t;
    }

So the error happends when the first Deserialize method is run, with the above error.

I have tried several things but I am quite lost on this one..

Thanks! :-)

Answer 1

I think the coversion back from base64 to bytes is wrong.

Try this:

var bytes = Convert.FromBase64String(base64);

=>

 MemoryStream recieverStream = new MemoryStream(Convert.FromBase64String(trace.Reciever));

  NPC reciever = formatter.Deserialize(recieverStream) as NPC;

Answer 2

I think it is because Convert.ToBase64String(recieverStream.ToArray()) and enc.GetBytes(trace.Reciever) are not each other counterparts.

You need do unencode the base64 in the decoding part.