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

Private Sub DownloadFile(relativeUrl As String, destinationPath As String, name As String)
    Try
        destinationPath = Replace(destinationPath + "\" + name, "\\", "\")
        Dim fi As FileInformation = Microsoft.SharePoint.Client.File.OpenBinaryDirect(Me.context, relativeUrl)
        Dim down As Stream = System.IO.File.Create(destinationPath)
        Dim a As Integer = fi.Stream.ReadByte()
        While a <> -1
            down.WriteByte(CType(a, Byte))
            a = fi.Stream.ReadByte()
        End While
    Catch ex As Exception
        ToLog(Type.ERROR, ex.Message)
    End Try
End Sub