i have a file list with check box for each files , if the user checks many files and click download i have to zip all those files and download it... like in mails attachment
The 3 libraries I know of are SharpZipLib (versatile formats), DotNetZip (everything ZIP), and ZipStorer (small and compact). No links, but they are all on codeplex and found via google. The licenses and exact features vary.