http://blogger.org.cn/blog/more.asp?name=nrzj&id=4280
using System;
 using System.Diagnostics;
namespace Tipo.Tools.Utility
 {
  /// <summary>
  /// 常用Dos命令操作
  /// </summary>
  public class DosCommand
  {
   private Process process=null;
   private string _errmsg;
  public DosCommand()
   {
    process = new Process();
    process.StartInfo.FileName = "cmd.exe";
    process.StartInfo.UseShellExecute = false;
    process.StartInfo.RedirectStandardInput = true;
    process.StartInfo.RedirectStandardOutput = true;
    process.StartInfo.RedirectStandardError = true;
    process.StartInfo.CreateNoWindow = false;
    process.Start();
   }
  //检测文件或目录是否存在
   public string exist(string path)
   {
    process.StandardInput.WriteLine(string.Format("dir \"{0}\"",path));
    process.StandardInput.WriteLine("exit");
    _errmsg = process.StandardError.ReadToEnd();
    return _errmsg;
   }
  }
 }