Distinguish between null and missing field when mapping (POCO) with mongodb

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Distinguish between null and missing field when mapping (POCO) with mongodb



Lets say i have a class


class Person

[BsonElement("name")]
public string Name get; set;

[BsonElement("age")]
public int? Age get; set;



then in mongo I have



[
"name": "Jan",
"age": null
,
"name": "San",
"age": 20
,
"age": 20
]



Then call


collection.Find(filter).Project<Person>(projections).ToListAsync()



and then I get back



[
"Name": "Jan",
"Age": null
,
"Name": "San",
"Age": 20
,
"Name": null,
"Age": 20
]



Is there a way to see if the field was missing and not just get null back









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