HOWTO：在pdfsplitter使用itext v7 api完成其工作后，以字节数组的形式检索pdfdocument？

Question

我设法根据VB.net并使用iText v7 api在这里和那里放了一些代码。但是，我在尝试将拆分后的文档重新获取为字节数组时遇到问题。非常感谢您的帮助。谢谢。对不起，我承认我是菜鸟，对编​​码还不熟悉。

    Private Sub SplitSub()
        Dim pdfcontents As New List(Of Byte())
        Dim reader As iText.Kernel.Pdf.PdfReader = New iText.Kernel.Pdf.PdfReader("C:\Users\XXX\Desktop\Test\Test.pdf")
        Dim pdfDoc As iText.Kernel.Pdf.PdfDocument = New iText.Kernel.Pdf.PdfDocument(reader)
        Dim splitter As ByteArrayPdfSplitter = New ByteArrayPdfSplitter(pdfDoc)
        Dim splitDocuments As List(Of iText.Kernel.Pdf.PdfDocument) = splitter.SplitBySize(5000000)
        For Each splitDoc In splitDocuments
            Dim bytecontents as Byte()
            '??? How do I retrieve the pdfDocuments as bytes()???
            pdfcontents.Add(bytecontents)
        Next
        pdfDoc.Close()
        reader.Close()
    End Sub


Class ByteArrayPdfSplitter
    Inherits iText.Kernel.Utils.PdfSplitter

    Private currentOutputStream As MemoryStream

    Public Sub New(ByVal pdfDocument As iText.Kernel.Pdf.PdfDocument)
        MyBase.New(pdfDocument)
    End Sub

    Protected Overrides Function GetNextPdfWriter(ByVal documentPageRange As iText.Kernel.Utils.PageRange) As iText.Kernel.Pdf.PdfWriter
        currentOutputStream = New MemoryStream()
        Return New iText.Kernel.Pdf.PdfWriter(currentOutputStream)
    End Function

    Public ReadOnly Property CurrentMemoryStream As MemoryStream
        Get
            Return currentOutputStream
        End Get
    End Property

    Public Class DocumentReadyListener
        Implements iText.Kernel.Utils.PdfSplitter.IDocumentReadyListener
        Private splitter As ByteArrayPdfSplitter

        Public Sub New(ByVal splitter As ByteArrayPdfSplitter)
            Me.splitter = splitter
        End Sub

        Public Sub DocumentReady(ByVal pdfDocument As iText.Kernel.Pdf.PdfDocument, ByVal pageRange As iText.Kernel.Utils.PageRange) Implements iText.Kernel.Utils.PdfSplitter.IDocumentReadyListener.DocumentReady
            pdfDocument.Close()
            Dim contents As Byte() = splitter.CurrentMemoryStream.ToArray()
        End Sub

    End Class