UNE SIMPLE CALCULATRICE

Public DernierChiffre As Double
Public Operation As Boolean
Public LeSigne As String
Public Virgule As Boolean

Private Sub CmdOperation_Click(Index As Integer)
If LeSigne <> "" Then Call Validation
    Select Case Index
        Case 0
            LeSigne = "+"
        Case 1
            LeSigne = "-"
        Case 2
            LeSigne = "x"
        Case 3
            LeSigne = "/"
        Case 4
            LeSigne = ""
            Exit Sub
        End Select
        DernierChiffre = TextChiffre.Text
        Operation = True
End Sub

Private Sub CmdReset_Click()
    DernierChiffre = 0
    Operation = False
    LeSigne = ""
    Virgule = False
    TextChiffre = "0"
End Sub
Private Sub Num_Click(Index As Integer)
    If Operation = True Then TextChiffre.Text = "0": Operation = False
    TextChiffre.Text = CDbl(TextChiffre.Text & Index)
End Sub

Private Sub NumVirg_Click()
    If Operation = True Then TextChiffre.Text = "0": Operation = False
    If Virgule <> True Then TextChiffre.Text = TextChiffre.Text & ",": Virgule = True
End Sub

Sub Validation()
        Select Case LeSigne
            Case "+"
                DernierChiffre = DernierChiffre + TextChiffre.Text
            Case "-"
                DernierChiffre = DernierChiffre - TextChiffre.Text
            Case "x"
                DernierChiffre = DernierChiffre * TextChiffre.Text
            Case "/"
                DernierChiffre = DernierChiffre / TextChiffre.Text
        End Select

    TextChiffre.Text = DernierChiffre
    Operation = True
    LeSigne = ""
    Virgule = False
End Sub