Visual Basic.NET - Convertir un archivo Gzip a base 64

Private Sub Compresion()

    ' Byte array from string.

    'Dim array() As Byte = Encoding.ASCII.GetBytes(New String("y"c, 10000))

    Dim array() As Byte = Encoding.ASCII.GetBytes(Convert.ToBase64String(convertir64))

    ' Call Compress.

    Dim c() As Byte = Compress(array)

    ' Write bytes.

    File.WriteAllBytes("E:\Pruebas web service vb\prueba_XML\compress.gz", c)

End Sub

''' <summary>

''' Receives bytes, returns compressed bytes.

''' </summary>

Function Compress(ByVal raw() As Byte) As Byte()

    ' Clean up memory with Using-statements.

    Using memory As MemoryStream = New MemoryStream()

        ' Create compression stream.

        Using gzip As GZipStream = New GZipStream(memory, CompressionMode.Compress, True)

            ' Write.

            gzip.Write(raw, 0, raw.Length)

        End Using

        ' Return array.

        Return memory.ToArray()

    End Using

End Function

Private Function convertir64()

    Dim value As String = File.ReadAllText("E:\trabajos\xml\mixml.xml")

    Dim byt As Byte() = System.Text.Encoding.UTF8.GetBytes(value)

    'MsgBox(value)

    MsgBox(Convert.ToBase64String(byt))

    Return byt

End Function