Get _id of an inserted document in MongoDB?

Question

say I have a product listing. When I add a new product I save it using something like

var doc=products.Insert(p);

The pro

Answer 1

class BsonID
{
    [BsonId]
    public ObjectId Id { get; set; }
}
var document = new BsonDocument {
   {"_id", new BsonID().Id },
   { "code", dr.Cells["code"].Value.ToString() },
   { "name", dr.Cells["name"].Value.ToString() },
  };
var customers = _database.GetCollection("Customers");
customers.InsertOne(document);
var id = document.ElementAt(0).Value.ToString();