MongoDB C#驱动程序-如何在.NET中的联接集合上强制投影？

var connectionString = "mongodb://localhost:27017";
var databaseName = "mydb";

var client = new MongoClient(connectionString);
var database = client.GetDatabase(databaseName);

var collectionName = "mycollection";
var collection = database.GetCollection<MyModel>(collectionName);

var result = collection.Find(x => x.Age > 18)
    .Project(x => new { x.Name, x.Age })
    .ToList();

var filter = Builders<MyModel>.Filter.Gt(x => x.Age, 18);
var projection = Builders<MyModel>.Projection.Include(x => x.Name).Include(x => x.Age);

var result = collection.Find(filter).Project(projection).ToList();