How to download document from SharePoint document library

Question

Hello Everyone,

While developing, I stuck to download the single document and also multiple document from SharePoint document library which is in Office 365 site.

I have created Sandbox Solution, while developing such things i observed SPFile.OpenBinaryStream is not available into sandbox solution (namespace Microsoft.SharePoint.dll).to get the file.
Do how to download single and multiple document from document library?

 

-- I tired also zip functionality using

http://www.sharepointanalysthq.com/2012/10/download-multiple-documents-for-sharepoint-2010/ 

--DeviantPoint.DownloadZip 

also but not getting any result.

 

Many Thanks,

Sumit