如何将文本附加到现有文件？

Question

以下代码帮助我解析PPT幻灯片的文本并将其转储到名为Project_SI Feedback_temp_v3.csv的csv文件中。此文件应该是我要转储文本的模板，而此代码打开一个名为Project_SI Feedback_temp_v3.csv的新csv文件，而不是将其写入给定模板。有什么办法可以打开现有文件而不是创建一个新文件吗？

  Sub ExportTextToCSV()

  Dim oPres As Presentation
  Dim oSlides As Slides
  Dim oSld As Slide         'Slide Object
  Dim oShp As Shape         'Shape Object
  Dim iFile As Integer      'File handle for output
  Dim sTempString As String

  Dim PathSep As String
  Dim Quote As String
  Dim Comma As String
  iFile = FreeFile          'Get a free file number

  #If Mac Then
    PathSep = ":"
  #Else
    PathSep = "\"
  #End If

  Quote = Chr$(34)
  Comma = ","

  Set oPres = ActivePresentation
  Set oSlides = oPres.Slides

  'Open output file
  ' NOTE:  errors here if original PPT file hasn't been saved
  Open oPres.Path & PathSep & "Project_SI Feedback_temp_v3.csv" For Output As iFile

  For Each oSld In oSlides    'Loop thru each slide
    For Each oShp In oSld.Shapes                'Loop thru each shape on slide

      'Check to see if shape has a text frame and text
      If oShp.HasTextFrame And oShp.TextFrame.HasText Then
          sTempString = sTempString & ",,," & Quote & oShp.TextFrame.TextRange.Text & Quote & Comma
      End If

    Next oShp

    ' print the result to file:
    Print #iFile, sTempString
    sTempString = ""

  Next oSld

  'Close output file
  Close #iFile