1 public class People 2 { 3 DateTime birthday, 4 string name, 5 string cardNo 6 } 7 8 9 List<People> peoples = new List<People>(); 10 peoples.Add(...); 11 peoples.Add(...); 12 ... 13 peoples.Add(...); 14 peoples = peoples.OrderBy(people=>people.birthday).ThenBy(people => people.cardNo).ToList();