Private Shared Sub ZipWriterExample()
      Dim zipFilePath As String = "D:\RealTimeZipExamples\MyZipFile.zip"
      ' NOTE: The trailing backslash is important, we use it below to build the paths in the zip archive
      Dim sourceFolder As String = "D:\ToZip\"

      ' Create a stream for a new zip file
      Using zipFileStream As New FileStream(zipFilePath, FileMode.Create, FileAccess.Write, FileShare.None)
'         Wrapping the ZipWriter object in a 'using' block will make sure the archive is closed
'         * properly after we're done adding content. If you use ZipWriter outside a 'using' block,
'         * make sure you call ZipWriter.CloseZipFile() to flush the archive's meta data
'         * to the output stream. 

        ' Create the ZipWriter object around the stream
        Using zipWriter As New ZipWriter(zipFileStream)
          Dim index As Integer
          Dim sourceFile As FileInfo
          Dim sourceFilenameInZip As String

'           As a convenience, ZipWriter offers the option to automatically close the output stream when
'             ZipWriter is closed. The behavior is disabled by default.
'         
'             In this example, we will not enable it because we are already closing the zip
'             file automatically in the 'using' block above. 
          'zipWriter.AllowOutputStreamClosure = true;

'           Since we'll be adding many files in the archive, we'll create a work buffer
'             ahead of time and use it over and over again to avoid creating a new buffer
'             each time we read from a source file. 
          Dim bufferSize As Integer = 64 * 1024
          Dim buffer(bufferSize - 1) As Byte

'           Create a local header object that will be used to specify the path/filename in
'             the zip file and other options like compression and encryption. 
          Dim localHeader As New ZipItemLocalHeader()

'           Options can be set "globally" before zipping starts.
'             We will set the file name for each file inside the loop. The other 
'             options have default values that satisfy us:
'             The compression method is Deflated at a the 'Normal' compression level
'             No encryption.
'             No comment. 
          'localHeader.CompressionMethod = CompressionMethod.Deflated;
          'localHeader.CompressionLevel = CompressionLevel.Normal;
          'localHeader.EncryptionMethod = EncryptionMethod.WinZipAes;
          'localHeader.EncryptionPassword = "password";

          ' Compute the index where the base path ends, minus the trailing backslash
          index = sourceFolder.Length - 1

          ' Go through all the files in the source folder and its sub-folders
          For Each sourcePath As String In Directory.EnumerateFiles(sourceFolder, "*", SearchOption.AllDirectories)
            ' Get file information
            sourceFile = New FileInfo(sourcePath)

            ' Compute a relative path for the file consisting of the full path minus the base path in 'sourceFolder'
            sourceFilenameInZip = sourcePath.Substring(index)

            ' Assign the filename in zip in the header
            localHeader.FileName = sourceFilenameInZip

            ' Optional. Set the last write date/time in the header
            localHeader.LastWriteDateTime = sourceFile.LastWriteTime

            Try
              ' Open the current file for sequential reading
              Using sourceFileStream As Stream = New FileStream(sourcePath, FileMode.Open, FileAccess.Read, FileShare.Read, bufferSize, FileOptions.SequentialScan)
'                 If we make it here, the source file has been opened successfully. We can
'                   safely add the item to the zip archive. 

                ' Write the local header for the file in the archive
                zipWriter.WriteItemLocalHeader(localHeader)

                ' Write the entire stream's content to the archive, using the work buffer we created
                zipWriter.WriteItemData(sourceFileStream, buffer, 0, bufferSize)
              End Using
            Catch e1 As FileNotFoundException
'               We're unable to open the source file. We will simply skip it and continue to
'                 the next one. 

            Catch e2 As System.Security.SecurityException
'               We're unable to open the source file. We will simply skip it and continue to
'                 the next one. 
            Catch e3 As DirectoryNotFoundException
'               We're unable to open the source file. We will simply skip it and continue to
'                 the next one. 
            Catch e4 As UnauthorizedAccessException
'               We're unable to open the source file. We will simply skip it and continue to
'                 the next one. 
            Catch e5 As PathTooLongException
'               We're unable to open the source file. We will simply skip it and continue to
'                 the next one. 
            End Try
          Next sourcePath
          
          ' OPTIONAL: A global comment for the zip archive can be set when closing the archive. By default, there is no comment.
          'Dim endHeader As New ZipEndHeader("Dynamically generated in <unknown> seconds")
          'zipWriter.CloseZipFile(endHeader)

          ' Because we are in a 'using' block, ZipWriter.Dispose() will take care of calling
          ' ZipWriter.CloseZipFile() for us if we don't do it here.

          '  When using ZipWrite outside of a 'using' block, ZipWriter.CloseZipFile() MUST be
          '  called explicitly or the zip file will be incomplete and unusable.
        End Using
      End Using
    End Sub

    Private Shared Function ZipWriterExampleXamarin() As Stream
'       NOTE: The zip file can be any type of stream you need. A network stream, a file stream, etc
'         The component will never call Stream.Seek() on the stream and will only write to it. 

      ' Create a writable stream for the zip file
      Dim zipFileStream As Stream = New MemoryStream()

'       Wrapping the ZipWriter object in a 'using' block will make sure the archive is closed
'         properly after we're done adding content. If you use ZipWriter outside a 'using' block,
'         make sure you call ZipWriter.CloseZipFile() to flush the archive's meta data
'         to the output stream. 

      ' Create the ZipWriter object around the stream
      Using zipWriter As New ZipWriter(zipFileStream)
'         As a convenience, ZipWriter offers the option to automatically close the output stream when
'           ZipWriter is closed. The behavior is disabled by default.
'         
'           In this example, we will not enable it as we want to manipulate the zip file
'           after it has been written. 
        'zipWriter.AllowOutputStreamClosure = true;

'         If we'll be adding many items in the archive, we'll create a work buffer
'           ahead of time and use it over and over again to avoid creating a new buffer
'           each time we read from a source file.
'          
'           This example doesn't add many items but still shows the technique. 
        Dim bufferSize As Integer = 64 * 1024
        Dim buffer(bufferSize - 1) As Byte

'         Create a local header object that will be used to specify the path/filename in
'           the zip file and other options like compression and encryption. 
        Dim localHeader As New ZipItemLocalHeader()

'         Options can be set "globally" before zipping starts.
'           We will set the file name for each file inside the loop. The other 
'           options have default values that satisfy us:
'           The compression method is Deflated at a the 'Normal' compression level
'           No encryption.
'           No comment. 
        'localHeader.CompressionMethod = CompressionMethod.Deflated;
        'localHeader.CompressionLevel = CompressionLevel.Normal;
        'localHeader.EncryptionMethod = EncryptionMethod.WinZipAes;
        'localHeader.EncryptionPassword = "password";

        ' Assign the filename in zip in the header
        localHeader.FileName = "MyFile1.dat"

        ' Optional. Set the last write date/time in the header
        localHeader.LastWriteDateTime = DateTime.Now

'         NOTE: The source data can be any type of stream you need. A network stream, a file stream, etc
'        The component will never call Stream.Seek() on the stream and will only read from it.
'       
'        This example will use memory data to keep it simple and on point. 

        ' Create some source data
        Dim dataToZip() As Byte = System.Text.Encoding.UTF8.GetBytes("The quick brown fox jumps over the lazy dog")

        ' Create a stream around the source data
        Using sourceDataStream As Stream = New MemoryStream(dataToZip, False)
          ' Write the local header for the file in the archive
          zipWriter.WriteItemLocalHeader(localHeader)

          ' Write the entire stream's content to the archive, using the work buffer we created
          zipWriter.WriteItemData(sourceDataStream, buffer, 0, bufferSize)
        End Using
      End Using

'       At this point, 'zipFileStream' contains a zip file. You can store it, upload it, etc as you
'         see fit. Because it is a stream, remember to change the current position to the start of the
'         stream if you wish to read the data. 

      zipFileStream.Seek(0, SeekOrigin.Begin)

      ' TODO: Send/store/whatever the zip file 

      Return zipFileStream
    End Function