不知道下面这个程序,是不是你想要的??????
using System;
using 
namespace _06_12
{
 public class Class_06_12
 {
  public static void Main()
  {
   string currentDir=Directory.GetCurrentDirectory ();
   string parentDir=Directory.GetParent (currentDir).Name ;
   string dirRoot=Directory.GetDirectoryRoot (currentDir);
   string[] rootDirs=Directory.GetDirectories (dirRoot);
   string[] rootFiles=Directory.GetFiles (dirRoot);
   string[] drives=Directory.GetLogicalDrives ();
   Console.WriteLine ("当前目录是:{0}",currentDir);
   Console.WriteLine ("当前目录的父目录是:{0}",parentDir);
   Console.WriteLine ("当前目录的根目录是:{0}",dirRoot);
   Console.WriteLine ("根目录下的子目录是:");
   foreach(string s in rootDirs)
   {
    Console.WriteLine (s);
   }
   Console.WriteLine ("所有的逻辑磁盘是:");
   foreach(string s in drives)
   {
    Console.WriteLine (s);
   }
  }
 }
}