ASP.NET

public void CreateZipFile(string sPath)
  {
    FileOutputStream stream1 = null;
    ZipOutputStream stream2 = null;
    if (System.IO.File.Exists(sPath))
    {
   FileInfo info2 = new FileInfo(sPath);
       stream1 = new FileOutputStream(sPath.Replace
                                     (info2.Extension, ".zip"));
   stream2 = new ZipOutputStream(stream1);
           this.ZipOneFile(stream1, stream2,  sPath);
    }
    else if (Directory.Exists(sPath))
    {
   stream1 = new FileOutputStream(sPath + ".zip");
   stream2 = new ZipOutputStream(stream1);
   DirectoryInfo info1 = new DirectoryInfo(sPath);
   this.ZipDirectory(stream1, stream2, info1, sPath);
    }
    stream2.close();
    stream1.close();
    stream2.flush();
    stream1.flush();
   }

   private void CopyStream(FileInputStream src, ZipOutputStream
                                                            dest)
   {
   InputStreamReader reader1 = new InputStreamReader(src);
   OutputStreamWriter writer1 = new OutputStreamWriter(dest);
   while (reader1.ready())
   {
     writer1.write(reader1.read());
   }
   writer1.flush();
   }

   /*ZipDirectory Method zips the entire directory*/
   private void ZipDirectory(FileOutputStream fos, ZipOutputStream
                            zos, DirectoryInfo di, string SRootDir)
   {
   FileInfo[] infoArray2 = di.GetFiles();
   foreach (FileInfo info2 in infoArray2)
   {
          ZipEntry entry1 = new ZipEntry
              (info2.FullName.Substring(SRootDir.LastIndexOf(@"\")));
      entry1.setMethod(8);
      zos.putNextEntry(entry1);
      FileInputStream stream1 = new FileInputStream
                                      (info2.FullName);
          this.CopyStream(stream1, zos);
      zos.closeEntry();
      stream1.close();
   }
   DirectoryInfo[] infoArray1 = di.GetDirectories();
   foreach (DirectoryInfo info1 in infoArray1)
   {
      this.ZipDirectory(fos, zos, info1, SRootDir);
   }
    }