private string WriteAndReadLenString(string val)
{
var ms = new MemoryStream();
var bs = new BsonWriter(ms, new BsonDocumentDescriptor());
var w = new BinaryWriter(ms);
var byteCount = bs.CalculateSize(val, false);
w.Write(byteCount);
bs.Write(val, false);
ms.Seek(0, SeekOrigin.Begin);
var reader = new BsonReader(ms, new BsonDocumentBuilder());
return(reader.ReadLengthString());
}
