Bonjour,
Dans un module de classe nommé Classe1 :
Public WithEvents App As Application
Private Sub App_WorkbookNewSheet(ByVal Wb As Workbook, ByVal Sh As Object)
MsgBox Sh.Name & " " & Wb.Worksheets.Count
End Sub
Dans ThisWorkbook :
Dim cls As New Classe1
Private Sub Workbook_Open()
Set cls = New Classe1
Set cls.App = Application
End Sub
Cordialement
ctac