压缩文件

         ZipFile zip = new ZipFile();

            zip.AddFile("c:\\666.txt");

            MemoryStream output = new MemoryStream();

            zip.Save(output);

            byte[] zipbytes = output.ToArray();

            FileStream fs = File.OpenWrite("c:\\666.zip");

            fs.Write(zipbytes, 0, zipbytes.Length);

            fs.Close();

Dll下载地址:http://files.cnblogs.com/ycdx2001/Ionic.Zip.Reduced.rar