Daniel Gustafsson Daniel Gustafsson - 1 month ago 8
C# Question

cannot do asqueryable on mongodb collection

I got two models, a User and a Team as below:

[BsonRepresentation(BsonType.ObjectId)]
public ObjectId _id { get; set; }
[Display(Name = "Password:")]
public string Password { get; set; }
[Display(Name = "Confirm:")]
public string ConfirmPassword { get; set; }
[Display(Name = "Email:")]
public string Email { get; set; }
[Display(Name = "Username:")]
public string UserName { get; set; }
[Display(Name = "Firtname:")]
public string Firstname { get; set; }
[Display(Name = "Lastname:")]
public string Lastname { get; set; }
[Display(Name = "Country:")]
public string Country { get; set; }
[Display(Name = "City:")]
public string City { get; set; }
[Display(Name = "Birthdate:")]
public int Birthdate { get; set; }
public List<Team> Teams { get; set; }


[BsonRepresentation(BsonType.ObjectId)]
public ObjectId TeamID { get; set; }
public string TeamName { get; set; }
public string UserName { get; set; }
public int LeagueID { get; set; }

public List<Player> Player { get; set; }


So I've created a user but now I want to add teams to my user.
This is the code I'm using:

var databaseClient = new MongoClient(Settings.Default.FantasySportsConnectionString);
var server = databaseClient.GetServer();
var database = server.GetDatabase("Users");
var collection = database.GetCollection<User>("users");

var user = collection.AsQueryable().First(o => o._id == Session["ID"]);

user.Teams.Add(new Team { TeamID = new ObjectId(), TeamName = "Some Team" });


But when I do this I get these errors:

1:
Instance argument: cannot convert from 'MongoDB.Driver.MongoCollection<SportsFantasy_2._0.Models.User>' to 'System.Collections.IEnumerable'


2:
'MongoDB.Driver.MongoCollection<SportsFantasy_2._0.Models.User>' does not contain a definition for 'AsQueryable' and the best extension method overload 'System.Linq.Queryable.AsQueryable(System.Collections.IEnumerable)' has some invalid arguments

Answer

You are missing a namespace, MongoDB.Driver.Linq, simply add that at the top:

using MongoDB.Driver.Linq;

That specific method is:

LinqExtensionMethods
{
    public static IQueryable<T> AsQueryable<T>(this MongoCollection<T> collection);
    //...
}