C#如何遍历一个文件夹下面所有的文件、包括子文件夹里面的文件？

C#如何遍历一个文件夹下面所有的文件、包括子文件夹里面的文件？

ArrayList GetAll(DirectoryInfo dir)//搜索文件夹中的文件
        {
            ArrayList FileList = new ArrayList();

            FileInfo[] allFile = dir.GetFiles();
            foreach (FileInfo fi in allFile)
            {
                FileList.Add(fi.Name);
            }

            DirectoryInfo[] allDir= dir.GetDirectories();
            foreach (DirectoryInfo d in allDir)
            {
                GetAll(d);
            }
            return FileList;
        }
 DirectoryInfo d = new DirectoryInfo(@"F:\");
  ArrayList Flst= GetAll(d);

using System;
 using System.Collections.Generic;
 using System.Text;
 using System.Collections;
 using System.IO;


 namespace bianli
 {
     class Program
     {
         static ArrayList FileList = new ArrayList();


         static ArrayList GetAll(DirectoryInfo dir)//搜索文件夹中的文件
         {        


             FileInfo[] allFile = dir.GetFiles();
             foreach (FileInfo fi in allFile)
             {
                 FileList.Add(fi.FullName);
             }


             DirectoryInfo[] allDir = dir.GetDirectories();
             foreach (DirectoryInfo d in allDir)
             {
                 GetAll(d);
             }
             return FileList;
         }
   
         static void Main(string[] args)
         {
             DirectoryInfo d = new DirectoryInfo(@"E:\test");
             ArrayList Flst = GetAll(d);
             foreach (string f in Flst)
             {
                 Console.WriteLine(f);
             }
         }
     }
 }