C# MongoDB Add Item to Dictionary
To add an item to a Dictionary field in a MongoDB collection - say JoinRequests of the Ride collection - treat the dictionary field an array and utilize the $push operator. I do not like the k, v extra outlining, but this is the only way I found that works with dots in the key. If you find an atomic way that can treat the dictionary as a Document and
not as an array of documents, please let me know.
Here is an example.
using Microsoft.Extensions.Options;
using MongoDB.Driver;
class Ride {
// ..
[BsonDictionaryOptions(DictionaryRepresentation.ArrayOfDocuments)]
public Dictionary<Email, Passenger> Passengers { get; set; } = new();
/*
{
"Passengers": [{ "k": Email, "v": Passenger }]
}
*/
}
public async Task<bool> AcceptJoinRequest(string rideId, string driver, string user) {
var updatePull = Builders<Ride>.Update.Pull(r => r.JoinRequests, user);
var update = updatePull.Update.Push(r => r.Passengers, new KeyValuePair<string, Passenger>(user, new Passenger()));
var res = await _ridesCollection.UpdateOneAsync(x => x.Driver == driver && x.Id == rideId && x.JoinRequests.Contains(user), update);
return res.IsModifiedCountAvailable && res.ModifiedCount > 0;
}