How to download/upload files from/to SharePoint 2013 using CSOM?

Question

I am developing a Win8 (WinRT, C#, XAML) client application (CSOM) that needs to download/upload files from/to SharePoint 2013.

How do I do the Download/Upload?

Answer 1

Upload a file

Upload a file to a SharePoint site (including SharePoint Online) using File.SaveBinaryDirect Method:

using (var clientContext = new ClientContext(url)) {      using (var fs = new FileStream(fileName, FileMode.Open))      {          var fi = new FileInfo(fileName);          var list = clientContext.Web.Lists.GetByTitle(listTitle);          clientContext.Load(list.RootFolder);          clientContext.ExecuteQuery();          var fileUrl = String.Format("{0}/{1}", list.RootFolder.ServerRelativeUrl, fi.Name);           Microsoft.SharePoint.Client.File.SaveBinaryDirect(clientContext, fileUrl, fs, true);      } } 

Download file

Download file from a SharePoint site (including SharePoint Online) using File.OpenBinaryDirect Method:

using (var clientContext = new ClientContext(url)) {       var list = clientContext.Web.Lists.GetByTitle(listTitle);      var listItem = list.GetItemById(listItemId);      clientContext.Load(list);      clientContext.Load(listItem, i => i.File);      clientContext.ExecuteQuery();       var fileRef = listItem.File.ServerRelativeUrl;      var fileInfo = Microsoft.SharePoint.Client.File.OpenBinaryDirect(clientContext, fileRef);      var fileName = Path.Combine(filePath,(string)listItem.File.Name);      using (var fileStream = System.IO.File.Create(fileName))      {                             fileInfo.Stream.CopyTo(fileStream);      } }