vba 控制excel奇怪的问题

Private Sub Form_Load()

Dim ex As Excel.Application

Dim exwbook As Excel.Workbook

Dim exsheet As Excel.Worksheet

Dim sheet As Excel.Worksheet

Set ex = CreateObject("Excel.Application")

'ex.Visible = True

Set exwbook = ex.Workbooks.Open(App.Path & "\SIFc.xls")

For Each sheet In exwbook.Sheets

sheet.Delete

Next

exwbook.Close

End Sub

很简单的程序，就是把sheet都删了，昨天搞还好用，现在死活不删了。 而且不报错

[461 byte] By [msdn] at [2007-11-19 9:53:20]