public void DeserializeProperty( BsonReader bsonReader, object obj, BsonPropertyMap propertyMap ) { var bsonType = bsonReader.PeekBsonType(); BsonRegularExpression value; if (bsonType == BsonType.Null) { bsonReader.ReadNull(propertyMap.ElementName); value = null; } else { string pattern, options; bsonReader.ReadRegularExpression(propertyMap.ElementName, out pattern, out options); value = new BsonRegularExpression(pattern, options); } propertyMap.Setter(obj, value); }