public void SerializeProperty(
     BsonWriter bsonWriter,
     object obj,
     BsonPropertyMap propertyMap
 )
 {
     var value = (BsonBinaryData) propertyMap.Getter(obj);
     if (value == null) {
         bsonWriter.WriteNull(propertyMap.ElementName);
     } else {
         bsonWriter.WriteBinaryData(propertyMap.ElementName, value.Bytes, value.SubType);
     }
 }
 public void SerializeProperty(
     BsonWriter bsonWriter,
     object obj,
     BsonPropertyMap propertyMap
 )
 {
     var value = (Guid) propertyMap.Getter(obj);
     bsonWriter.WriteBinaryData(propertyMap.ElementName, value.ToByteArray(), BsonBinarySubType.Uuid);
 }