我试图创建一个VBA代码，它可以帮助我打开一个演示文稿，转到每个幻灯片，检查一个图表，然后复制其最小值和最大值在Excel工作表。我有一个40+幻灯片演示文稿与多个图表，这个代码将帮助我检查是否在所有图表轴值是一致的。下面是我正在工作的代码。到目前为止，能够打开演示文稿，但无法打开图表并将值复制到Excel。请帮助，VBA编码新手

Sub CopySlidechart()

    Dim ppApp As PowerPoint.Application
    Dim ppPres As PowerPoint.Presentation
    Dim ppSlide As PowerPoint.Slide
    Dim ppPlaceHolder As PowerPoint.Shape
    Dim oRow As Long

    Set ppApp = CreateObject("PowerPoint.Application")
    Set ppApp = New PowerPoint.Application
    ppApp.Visible = msoTrue
    
    Dim input_path As String
    input_path = ThisWorkbook.Worksheets("Sheet1").Range("B1")

    Set ppPres = ppApp.Presentations.Open(input_path)

    oRow = 6
    For Each ppSlide In ppPres.Slides
        For Each ppPlaceHolder In ppSlide.Shapes
            If ppPlaceHolder.HasChart Then
            ThisWorkbook.Worksheets("Sheet1").Range(oRow, "B").Value = ChartObject.Chart.Axes(xlCategory).MaximumScale
            ThisWorkbook.Worksheets("Sheet1").Cells(oRow, "C").Value = ChartObject.Chart.Axes(xlCategory).MinimumScale
    oRow = oRow + 1
                oRow = oRow + 1
                Exit For
            End If
        Next ppPlaceHolder
    Next ppSlide

End Sub