WriteUndefined() публичный абстрактный Метод

Writes a BSON undefined to the writer.
public abstract WriteUndefined ( ) : void
Результат void
 /// <summary>
 /// Serializes an object to a BsonWriter.
 /// </summary>
 /// <param name="bsonWriter">The BsonWriter.</param>
 /// <param name="nominalType">The nominal type.</param>
 /// <param name="value">The object.</param>
 /// <param name="options">The serialization options.</param>
 public override void Serialize(
     BsonWriter bsonWriter,
     Type nominalType,
     object value,
     IBsonSerializationOptions options
 ) {
     if (value == null) {
         bsonWriter.WriteNull();
     } else {
         bsonWriter.WriteUndefined();
     }
 }
        /// <summary>
        /// Serializes an object to a BsonWriter.
        /// </summary>
        /// <param name="bsonWriter">The BsonWriter.</param>
        /// <param name="nominalType">The nominal type.</param>
        /// <param name="value">The object.</param>
        /// <param name="options">The serialization options.</param>
        public override void Serialize(
            BsonWriter bsonWriter,
            Type nominalType,
            object value,
            IBsonSerializationOptions options)
        {
            if (value == null)
            {
                bsonWriter.WriteNull();
            }
            else
            {
                var bsonDateTime = (BsonDateTime)value;
                var dateTimeSerializationOptions = EnsureSerializationOptions<DateTimeSerializationOptions>(options);

                DateTime utcDateTime = DateTime.MinValue;
                long millisecondsSinceEpoch;
                if (dateTimeSerializationOptions.DateOnly)
                {
                    if (bsonDateTime.Value.TimeOfDay != TimeSpan.Zero)
                    {
                        throw new BsonSerializationException("TimeOfDay component is not zero.");
                    }
                    utcDateTime = DateTime.SpecifyKind(bsonDateTime.Value, DateTimeKind.Utc); // not ToLocalTime
                    millisecondsSinceEpoch = BsonUtils.ToMillisecondsSinceEpoch(utcDateTime);
                }
                else
                {
                    if (bsonDateTime.IsValidDateTime)
                    {
                        utcDateTime = BsonUtils.ToUniversalTime(bsonDateTime.Value);
                    }
                    millisecondsSinceEpoch = bsonDateTime.MillisecondsSinceEpoch;
                }

                switch (dateTimeSerializationOptions.Representation)
                {
                    case BsonType.DateTime:
                        bsonWriter.WriteDateTime(millisecondsSinceEpoch);
                        break;
                    case BsonType.Document:
                        bsonWriter.WriteStartDocument();
                        bsonWriter.WriteDateTime("DateTime", millisecondsSinceEpoch);
                        if (bsonDateTime.IsValidDateTime)
                        {
                            bsonWriter.WriteInt64("Ticks", utcDateTime.Ticks);
                        }
                        else
                        {
                            bsonWriter.WriteUndefined("Ticks");
                        }
                        bsonWriter.WriteEndDocument();
                        break;
                    case BsonType.Int64:
                        if (bsonDateTime.IsValidDateTime)
                        {
                            bsonWriter.WriteInt64(utcDateTime.Ticks);
                        }
                        else
                        {
                            throw new BsonSerializationException("BsonDateTime is not a valid DateTime.");
                        }
                        break;
                    case BsonType.String:
                        if (dateTimeSerializationOptions.DateOnly)
                        {
                            bsonWriter.WriteString(bsonDateTime.Value.ToString("yyyy-MM-dd"));
                        }
                        else
                        {
                            // we're not using XmlConvert.ToString because of bugs in Mono
                            var dateTime = bsonDateTime.Value;
                            if (dateTime == DateTime.MinValue || dateTime == DateTime.MaxValue)
                            {
                                // serialize MinValue and MaxValue as Unspecified so we do NOT get the time zone offset
                                dateTime = DateTime.SpecifyKind(dateTime, DateTimeKind.Unspecified);
                            }
                            else if (dateTime.Kind == DateTimeKind.Unspecified)
                            {
                                // serialize Unspecified as Local se we get the time zone offset
                                dateTime = DateTime.SpecifyKind(dateTime, DateTimeKind.Local);
                            }
                            bsonWriter.WriteString(dateTime.ToString("yyyy-MM-ddTHH:mm:ss.FFFFFFFK"));
                        }
                        break;
                    default:
                        var message = string.Format("'{0}' is not a valid DateTime representation.", dateTimeSerializationOptions.Representation);
                        throw new BsonSerializationException(message);
                }
            }
        }
        /// <summary>
        /// Serializes an object to a BsonWriter.
        /// </summary>
        /// <param name="bsonWriter">The BsonWriter.</param>
        /// <param name="nominalType">The nominal type.</param>
        /// <param name="value">The object.</param>
        /// <param name="options">The serialization options.</param>
        public override void Serialize(
            BsonWriter bsonWriter,
            Type nominalType,
            object value,
            IBsonSerializationOptions options)
        {
            if (value == null)
            {
                throw new ArgumentNullException("value");
            }

            bsonWriter.WriteUndefined();
        }