DirectoryInfo

using System;
using System.IO;
using System.Linq;
using System.Text;

class Program
{
    static void Main()
    {
        DirectoryInfo di = new DirectoryInfo(@"c:\photos");

        foreach (FileInfo fi in di.GetFiles("*.jpg")) 
            Console.WriteLine(fi.Name);

        foreach (DirectoryInfo subDir in di.GetDirectories()) 
            Console.WriteLine(subDir.FullName);
    }
}