Sub Commentaire()
'indique dans un commentaire les dates des contrôles techniques
Dim r As Range, liste As String
Set r = Feuil10.Range("M2:M4,N2:N3")
For Each r In r
liste = liste & IIf(r <> "", vbLf & r, "")
Next
liste = Mid(liste, 2)
With [G3]
If Not .Comment Is Nothing Then .Comment.Delete
.AddComment liste
.Comment.Shape.TextFrame.AutoSize = True
.Interior.ColorIndex = IIf(liste = "", xlNone, 3) 'cellule en rouge
End With
End Sub