using System.Collections.Generic;
using System.IO;
using System.Linq;

class SortFiles
{
    public IEnumerable<FileInfo> Sort()
    {
        // Set the directory you want to search
        DirectoryInfo di = new DirectoryInfo(@"C:\"); 

        // Get all of the .jpg files from the directory and order
        // them by file name in descending order
        IEnumerable<FileInfo> files =
            di.GetFiles("*.jpg").OrderByDescending(e => e.Name); 

        return files;
    }
}