Private Sub Workbook_SheetActivate(ByVal Sh As Object)
Dim nom1$, nom2$, i%
nom1 = "Feuil1" 'à adapter
nom2 = "Feuil2" 'à adapter
Application.ScreenUpdating = False
Application.DisplayAlerts = False
If Sh.Name = nom1 Then
i = Sheets(nom1).Index
Sheets(nom2).Copy Before:=Sheets(nom1)
Sheets(nom1).Delete
Sheets(i).Name = nom1
ElseIf Sh.Name = nom2 Then
i = Sheets(nom2).Index
Sheets(nom1).Copy Before:=Sheets(nom2)
Sheets(nom2).Delete
Sheets(i).Name = nom2
End If
End Sub