Private Sub Worksheet_Change(ByVal Target As Range)
Application.ScreenUpdating = False
If Target.Address = "$A$1" Then
Select Case Target.Text
Case Is = "A"
Sheets("Feuil2").CommandButton1.Caption = "Bonjour"
Case Is = "B"
Sheets("Feuil2").CommandButton1.Caption = "Coucou"
Case Is = "C"
Sheets("Feuil2").CommandButton1.Caption = "Blabla"
End Select
Range("A1").Select
End If
Application.ScreenUpdating = True
End Sub