TestSerializeUserIdAsInt.cs

gistfile1.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

using MongoDB.Bson;
using MongoDB.Bson.DefaultSerializer;
using MongoDB.Bson.IO;
using MongoDB.Bson.Serialization;
using MongoDB.Driver;

namespace TestSerializeUserIdAsInt {
    public class UserId {
        static UserId() {
            BsonSerializer.RegisterSerializer(typeof(UserId), new UserIdSerializer());
        }

        public int Id { get; set; }
        public UserId(int id) {
            Id = id;
        }
    }

    public class User {
        [BsonId]
        public UserId UserId { get; set; }
        public string FirstName { get; set; }
        public string LastName { get; set; }
    }

    public class UserIdSerializer : BsonBaseSerializer {
        public override object Deserialize(BsonReader bsonReader, Type nominalType) {
            return new UserId(bsonReader.ReadInt32());
        }

        public override void Serialize(BsonWriter bsonWriter, Type nominalType, object value, bool serializeIdFirst) {
            var userId = (UserId) value;
            bsonWriter.WriteInt32(userId.Id);
        }
    }

    public static class Program {
        public static void Main(string[] args) {
            var server = MongoServer.Create("mongodb://localhost/?safe=true");
            var database = server["test"];
            var users = database.GetCollection<User>("users");

            var user = new User { UserId = new UserId(5678), FirstName = "John", LastName = "Doe" };
            users.RemoveAll();
            users.Insert(user);

            user = users.FindOne();
        }
    }
}