private void Serialize(BsonWriter bsonWriter, object value)
{
var serializer = _serializer;
var actualType = (value == null) ? _nominalType : value.GetType();
if (actualType != _nominalType)
{
serializer = BsonSerializer.LookupSerializer(actualType);
}
serializer.Serialize(bsonWriter, _nominalType, value, _serializationOptions);
}
}