Wire.SerializerSession.TryGetObjectId C# (CSharp) Method

        public bool TryGetObjectId(object obj, out int objectId)
        {
            return _objects.TryGetValue(obj, out objectId);
        }

 public static void WriteObject(this Stream stream, object value, Type valueType, ValueSerializer valueSerializer,
     bool preserveObjectReferences, SerializerSession session)
 {
     if (value == null) //value is null
     {
         NullSerializer.Instance.WriteManifest(stream, null, session);
     }
     else
     {
         int existingId;
         if (preserveObjectReferences && session.TryGetObjectId(value, out existingId))
         {
             //write the serializer manifest
             ObjectReferenceSerializer.Instance.WriteManifest(stream, null, session);
             //write the object reference id
             ObjectReferenceSerializer.Instance.WriteValue(stream, existingId, session);
         }
         else
         {
             var vType = value.GetType();
             var s2 = valueSerializer;
             if (vType != valueType)
             {
                 //value is of subtype, lookup the serializer for that type
                 s2 = session.Serializer.GetSerializerByType(vType);
             }
             //lookup serializer for subtype
             s2.WriteManifest(stream, vType, session);
             s2.WriteValue(stream, value, session);
         }
     }
 }