public KeyParameters(Asn1Sequence seq) { Attributes = seq?.OfType <DerBitString>().FirstOrDefault(); Algorithm = seq?.OfType <Asn1TaggedObject>() .Where(x => x.TagNo == 0) .Select(x => AlgorithmIdentifier.GetInstance(x, false)) .FirstOrDefault(); if (Algorithm == null) { throw new CryptographicException("Ошибка в данных параметров ключа."); } }