MemoryStream ms = new MemoryStream();
            byte[] buffer = null;
 using (ZipFile file = ZipFile.Create(ms))
            {
                file.BeginUpdate();
                file.NameTransform = new MyNameTransform();

                if (Directory.Exists(Path.GetDirectoryName(newpath)))
                {
                    DirectoryInfo dir = new DirectoryInfo(newpath);
                    FileInfo[] files=dir.GetFiles();
                    for (int i = 0; i < files.Length; i++)
                    {
                        file.Add(files[i].FullName);
                    }
                }

                file.CommitUpdate();
                buffer = new byte[ms.Length];
                ms.Position = 0;
                ms.Read(buffer, 0, buffer.Length);
            }


    Response.ContentType = "application/octet-stream";
 HttpBrowserCapabilities bc = Request.Browser;
 if (bc.Browser == "IE")
            {
                Response.AddHeader("Content-Disposition", "attachment; filename=" + HttpUtility.UrlEncode("考生照片.zip", System.Text.Encoding.UTF8));
            }
            else
            {
                Response.AddHeader("Content-Disposition", "attachment; filename=考生照片.zip");
            }
            
            Response.BinaryWrite(buffer);
            Response.Flush();
           
            DeleteFolder(newpath);
            Response.End();