Is there a way to retrieve a whole document, not just some of it's properties or collections?

For a json file from a docs' sample:

{
  "selected_user": { "id": 1, "name": "Phil", "age": 40, "city": "NY" },
  "temperature": 23.45,
  "note": "this is a test"
}

How could one retrieve it a as a whole into an instance of a class?

public class Settings
{
    public User SelectedUser { get; set; }
    public double Temperature { get; set; }
    public string Note { get; set; }
}