using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

public class Program

{

    public static void Main()

    {

        var list = CreateTestData();

        Console.WriteLine("Before\n--------");

        PrintList(list);

        var sorted = SortBy(list, x => x.Test, SortDirection.Descending);

        Console.WriteLine("After\n--------");

        PrintList(sorted);

    }

​

    static void PrintList(IEnumerable<SomeType> items)

    {

        foreach (var item in items)

        {

            Console.WriteLine(item.Test);

        }

        Console.WriteLine("--------");

    }

    static IList<TSource> SortBy<TSource, TMember>(IEnumerable<TSource> list, Func<TSource, TMember> selector, SortDirection direction)

    {

        if (direction == SortDirection.Descending)

            return list.OrderByDescending(selector).ToList();

        else

            return list.OrderBy(selector).ToList();

    }

​

    static IList<SomeType> CreateTestData()

    {

        var result = new List<SomeType>(10);

        for (int i = 0; i <= 9; i++)

        {

            result.Add(new SomeType { Test = ((char)65 + i).ToString() });

        }

        return result;

    }

}

​

public class SomeType

{

    public string Test { get; set; }

}

​

public enum SortDirection

{

    Ascending = 0,

    Descending = 1

}