MongoDb c# 2.0 driver AddToSet method

Question

I have the following code which was implemeted with MongoDb 2.0 c# driver. But I need to access to the MailLists collection of Profile which will be inserted. I've written the expected solution using p in constructor, but how to implement it via multiple operation?

IMongoCollection<Profile> dbCollection = DetermineCollectionName<Profile>();

var filter = Builders<Profile>.Filter.In(x => x.ID, profiles.Select(x => x.ID));

var updateMl = Builders<Profile>.Update.AddToSet(p => p.MailLists, new Profile2MailList
                        {
                            MailListId = maillistId,
                            Status = p.MailLists.MergeMailListStatuses(),
                            SubscriptionDate = DateTime.UtcNow
                        });
        
dbCollection.UpdateManyAsync(filter, updateMl, new UpdateOptions { IsUpsert = true });

Answer 1

I found the following solution:

IMongoCollection<Profile> dbCollection = DetermineCollectionName<Profile>();

var filter = Builders<Profile>.Filter.In(x => x.ID, profiles.Select(x => x.ID));

var profile2maillists = new List<Profile2MailList>();

foreach(var profile in profiles)
 {
     profile2maillists.Add(
         new Profile2MailList
                 {
                            MailListId = maillistId,
                            Status = profile.MailLists.MergeMailListStatuses(),
                            SubscriptionDate = DateTime.UtcNow
                 });
 }
var updateMl = Builders<Profile>.Update.AddToSetEach(p => p.MailLists, profile2maillists);
dbCollection.UpdateManyAsync(filter, updateMl, new UpdateOptions { IsUpsert = true });