GdPicture.NET可以將多頁PDF文件轉(zhuǎn)換為多頁TIFF文件，但是很多人在此之后都是對生成的文件進行物理保存。實際上在使用GdPicture.NET的時候，可以從PDF Stream中加載，并直接轉(zhuǎn)換為Tiff Stream，在實際操作性上方便了不少。

》》》下載GdPicture.NET最新試用版

示例代碼如下：

    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
      Dim oGdPictureImaging As New GdPicture.GdPictureImaging
      Dim MultiTiffID As Integer

      oGdPictureImaging.SetLicenseNumber("XXX")

      Dim PdfID As Integer = oGdPictureImaging.PdfReaderLoadFromFile("c:\test.pdf")

      If PdfID <> 0 Then
         For i As Integer = 1 To oGdPictureImaging.PdfReaderGetPageCount(PdfID)
            If oGdPictureImaging.GetStat = GdPicture.GdPictureStatus.OK Then
               oGdPictureImaging.PdfReaderSelectPage(PdfID, i)
               Dim RasterizedPageID As Integer = oGdPictureImaging.PdfReaderRenderPageToGdPictureImage(PdfID, 200, True) '200 DPI, can be changed.

               If i = 1 Then
                  MultiTiffID = oGdPictureImaging.TiffCreateMultiPageFromGdPictureImage(RasterizedPageID)
               Else
                  oGdPictureImaging.TiffAppendPageFromGdPictureImage(MultiTiffID, RasterizedPageID)
               End If
               oGdPictureImaging.ReleaseGdPictureImage(RasterizedPageID)
            End If
         Next

         Dim strm As New IO.MemoryStream
         oGdPictureImaging.SaveAsStream(MultiTiffID, strm, GdPicture.DocumentFormat.DocumentFormatTIFF, 65536)
         oGdPictureImaging.ReleaseGdPictureImage(MultiTiffID)
         oGdPictureImaging.PdfReaderCloseDocument(PdfID)
      End If
   End Sub