Private Sub Worksheet_Change(ByVal Target As Range)
Dim L As Byte
Dim P As String
If Not Intersect(Range("F8:F888"), Target) Is Nothing Then
On Error Resume Next
L = Len(Target.Value)
If L = 4 Then P = Right(Target, 3)
If L = 3 Then P = Right(Target, 2)
If L = 2 Then P = Right(Target, 1)
Select Case L
Case 1
If Left(Target, 1) = "C" Then MsgBox " Saisir un numéro en plus de la Lettre"
If Left(Target, 1) = "D" Then MsgBox " Saisir un numéro en plus de la Lettre"
If Left(Target, 1) = "R" Then MsgBox " Saisir un numéro en plus de la Lettre"
If Left(Target, 1) = "T" Then MsgBox " Saisir un numéro en plus de la Lettre"
If Left(Target, 1) = "c" Then MsgBox " Saisir un numéro en plus de la Lettre"
If Left(Target, 1) = "d" Then MsgBox " Saisir un numéro en plus de la Lettre"
If Left(Target, 1) = "r" Then MsgBox " Saisir un numéro en plus de la Lettre"
If Left(Target, 1) = "t" Then MsgBox " Saisir un numéro en plus de la Lettre"
Case 2
If Left(Target, 1) = "C" Then Target = Target & "00" & P
If Left(Target, 1) = "D" Then Target = Target & "00" & P
If Left(Target, 1) = "R" Then Target = Target & "00" & P
If Left(Target, 1) = "T" Then Target = Target & "00" & P
If Left(Target, 1) = "c" Then Target = UCase(Left(Target, 1)) & "00" & P
If Left(Target, 1) = "d" Then Target = UCase(Left(Target, 1)) & "00" & P
If Left(Target, 1) = "r" Then Target = UCase(Left(Target, 1)) & "00" & P
If Left(Target, 1) = "t" Then Target = UCase(Left(Target, 1)) & "00" & P
Case 3
If Left(Target, 1) = "C" Then Target = Target & "0" & P
If Left(Target, 1) = "D" Then Target = Target & "0" & P
If Left(Target, 1) = "R" Then Target = Target & "0" & P
If Left(Target, 1) = "T" Then Target = Target & "0" & P
If Left(Target, 1) = "c" Then Target = UCase(Left(Target, 1)) & "0" & P
If Left(Target, 1) = "d" Then Target = UCase(Left(Target, 1)) & "0" & P
If Left(Target, 1) = "r" Then Target = UCase(Left(Target, 1)) & "0" & P
If Left(Target, 1) = "t" Then Target = UCase(Left(Target, 1)) & "0" & P
Case 4
If Left(Target, 1) = "c" Then Target = UCase(Left(Target, 1)) & P
If Left(Target, 1) = "d" Then Target = UCase(Left(Target, 1)) & P
If Left(Target, 1) = "r" Then Target = UCase(Left(Target, 1)) & P
If Left(Target, 1) = "t" Then Target = UCase(Left(Target, 1)) & P
End Select
End If
End Sub