功能问题

Question

我试图让工作表已经存在的警报工作，但是，我迷路了。 函数定义不正确还是？

 Public Sub CopySheets()

    Do

        shName = InputBox("Please enter name of new project", "New Project")

        If shName <> "" Then

        shExists = SheetExists(shName) 'Check for existing sheet name
        If Not shExists Then
        Worksheets(Array(1, 2)).Copy After:=Sheets(Sheets.Count)


        Else

        MsgBox "Project Name:" & Space(1) & shName & " already exists", vbOKOnly + vbCritical, "Deter"
        End If
        End If
    Loop Until Not shExists Or shName = ""
End Sub

Private Function SheetExists(ByVal sheetName As String, _
        Optional ByVal wb As Workbook)

        If wb Is Nothing Then Set wb = ActiveWorkbook
        On Error Resume Next
        SheetExists = Not wb.Worksheets(sheetName) Is Nothing

End Function

Answer 1

您忘记添加函数的类型。 它必须是boolean

    Private Function 

    SheetExists(ByVal sheetName As String, _
        Optional ByVal wb As Workbook) As Boolean

        If wb Is Nothing Then Set wb = ActiveWorkbook
        On Error Resume Next
        SheetExists = Not wb.Worksheets(sheetName) Is Nothing

    End Function

您的代码的问题是，如果工作表不存在，行SheetExists = Not wb.Worksheets(sheetName) Is Nothing将引发错误，并且SheetExists将保留其默认值为空作为函数的默认数据类型，而没有定义数据类型是variant 。 如果您将数据类型定义为boolean则默认值将为False 。

恕我直言，这段代码虽然更长但更清晰

Private Function SheetExists(ByVal sheetName As String, _
    Optional ByVal wb As Workbook) As Boolean

    Dim ws As Worksheet

    If wb Is Nothing Then Set wb = ActiveWorkbook

    On Error GoTo EH
    Set ws = wb.Worksheets(sheetName)
    SheetExists = True

    Exit Function

EH:
    SheetExists = False

End Function