Private Sub Worksheet_SelectionChange(ByVal Target As Range)
Dim valeur As Variant
Dim Max As Integer
Dim ValeurCible As Variant
Dim CelluleTrouvee As Range
valeur = Target.Value
Max = Worksheets("Demandes").Range("A2").End(xlDown).Row
With Worksheets("Demandes").Range(Cells(3, 3), Cells(Max, 3))
Set CelluleTrouvee = .Find(valeur)
End With
ValeurCible = Cells(CelluleTrouvee.Row, CelluleTrouvee.Column + 2).Value
Target.Cells(1, 1).AddComment CStr(ValeurCible)
End Sub