class Employee:IComparable     {         public string Name { get; set; }         public int Age { get; set; }         public static List<Employee> GetEmployees()         {             return new List<Employee>()             {                 new Employee(){Name ="GuoHu",Age =25},                 new Employee(){Name ="LeiHu",Age =23},                 new Employee(){Name ="JunWenLi",Age =24},                 new Employee(){Name ="JinHaoLiu",Age =25},                 new Employee(){Name ="ChengFang",Age =24}             };         }         public int CompareTo(object obj)         {             Employee employee = obj as Employee;             if (employee != null)             {                 return Name.CompareTo(employee.Name);             }             else             {                 throw new ArgumentException("obj is not Employee");             }         }     }     class Test     {         static void SortAndShowFiles(string title, Comparison<Employee> employeeInfo)         {             List<Employee> employee = Employee.GetEmployees();             employee.Sort(employeeInfo);             Console.WriteLine(title);             foreach(Employee e in employee)             {                 Console.WriteLine("Name:{0},Age:{1}", e.Name, e.Age);             }         }         static void Main()         {             List<Employee> employeeInfo = Employee.GetEmployees();             //Using IComparable sort             employeeInfo.Sort();             employeeInfo.ForEach(e => Console.WriteLine("Name:{0},Age{1}/t", e.Name, e.Age));             SortAndShowFiles("Sort by name", delegate(Employee e1, Employee e2) { return e1.Name.CompareTo(e2.Name); });             SortAndShowFiles("Sort by age", delegate(Employee e1, Employee e2) { return e1.Age.CompareTo(e2.Age); });         }     }