MongoDB.Bson.Serialization.Serializers.BitmapSerializer.Deserialize C# (CSharp) Метод

        public override object Deserialize(
            BsonReader bsonReader,
            Type nominalType,
            Type actualType,
            IBsonSerializationOptions options)
        {
            if (nominalType != typeof(Image) && nominalType != typeof(Bitmap))
            {
                var message = string.Format("Nominal type must be Image or Bitmap, not {0}.", nominalType.FullName);
                throw new ArgumentException(message, "nominalType");
            }

            if (actualType != typeof(Bitmap))
            {
                var message = string.Format("Actual type must be Bitmap, not {0}.", actualType.FullName);
                throw new ArgumentException(message, "actualType");
            }

            var bsonType = bsonReader.GetCurrentBsonType();
            byte[] bytes;
            switch (bsonType)
            {
                case BsonType.Null:
                    bsonReader.ReadNull();
                    return null;

                case BsonType.Binary:
                    bytes = bsonReader.ReadBytes();
                    break;

                case BsonType.Document:
                    bsonReader.ReadStartDocument();
                    bsonReader.ReadString("_t");
                    bytes = bsonReader.ReadBytes("bitmap");
                    bsonReader.ReadEndDocument();
                    break;

                default:
                    var message = string.Format("BsonType must be Null, Binary or Document, not {0}.", bsonType);
                    throw new FileFormatException(message);
            }

            var stream = new MemoryStream(bytes);
            return new Bitmap(stream);
        }