无法从 excel 中删除工作表，使用 VB.NET 甚至没有错误？

Question

我有：

Public Class ExcelProcess
    Private App As New Excel.Application
    Private Books As Excel.Workbooks = App.Workbooks
    Private WB As Excel.Workbook

Public Sub deleteSheets()
    Dim sheet As Excel.Worksheet = getSheetToDelete()
    sheet.Activate()
    sheet.Delete()
    WB.Save()
    WB.Close()
End Sub

Private Function getSheetToDelete() As Excel.Worksheet
     Try
        WB = Books.Open("file.xlsx")
    Catch ex As Exception
        InputOutput.print(ex.Message)
        End
    End Try
    Return WB.Sheets(1)
End Function

End Class

我运行了上面的代码，运行成功，绝对没有错误或异常！

但工作表没有被删除！

我也试过了：

sheet.Select()
sheet.Delete()

' Now, this gave me an exception:
Unhandled Exception: System.Runtime.InteropServices.COMException: Exception from HRESULT: 0x800A03EC
at Microsoft.Office.Interop.Excel._Worksheet.Select(Object Replace)
at DealerCapReport.ExcelProcess.deleteSheets()
at DealerCapReport.MainModule.Main()

我尝试检查 sheet.Delete() 布尔值是否成功：

If sheet.Delete() Then        ' Error: Expression does not produce a value.
    Console.WriteLine("Can-not Delete")
End If

它说 Error: Expression does not generate a value. 在 sheet.Delete() 中。

奇怪的是Microsoft API reference 说它会产生一个布尔值，但它不会，因为它是一个 Sub 而不是一个函数。

发生了什么以及发生了什么？

我做错了吗？

请帮我解决这个问题！

Answer 1

以下代码对我有用（已编辑以包含一些错误检查）：

Public Class ExcelProcess
    Private xlApp As Excel.Application
    Private xlBook As Excel.Workbook
    Private xlSheet As Excel.Worksheet

    Public Sub New(ByVal file As String)
        xlApp = New Excel.Application
        'xlApp.Visible = True 'for debugging
        xlApp.DisplayAlerts = False 'prevent user dialogs
        xlBook = xlApp.Workbooks.Open(file)
    End Sub

    Public Sub Quit()
        If Not IsNothing(xlBook) Then
            xlBook.Save()
            xlBook.Close()
        End If
        If Not IsNothing(xlApp) Then xlApp.Quit()
    End Sub

    Public Sub deleteSheet(ByVal Index As Integer)
        If Index > xlBook.Worksheets.Count Then
            Throw New Exception("You cannot delete a worksheet that does not exist")
            Exit Sub
        End If
        If xlBook.Worksheets.Count = 1 Then
            Throw New Exception("You cannnot delete the only worksheet in a workbook")
            Exit Sub
        End If
        xlSheet = CType(xlBook.Worksheets(Index), Excel.Worksheet)
        xlSheet.Activate()
        xlSheet.Delete()
    End Sub

End Class

Answer 2

我建议您在删除后需要保存工作簿（使用SaveAs）。否则它只会删除内存中的工作表，当您的 Excel 对象超出范围时，它只会关闭工作簿而不保存更改。

Books.SaveAs(...)