public string GetFile()
{//获取根目录下的所以文件
  string Files = "";
  string[] Wenjian = Directory.GetFiles(Server.MapPath("~/"));
  foreach (string item in Wenjian)
  {
    FileInfo info = new FileInfo(item);
    Files += "文件名：" + info.Name + ";文件类型" + info.Extension + ";文件大小：" + info.Length + ";创建时间：" + info.CreationTime + "<br/>";
  }
  return Files;
}
public string Folder()
{//获取根目录下的所以文件夹
  string Folders = "";
  string[] wj = Directory.GetDirectories(Server.MapPath("~/"));
  foreach (string item in wj)
  {
    DirectoryInfo info = new DirectoryInfo(item);
    Folders += "文件夹名称：" + info.Name + "<br/>";
  }
  return Folders;
}