Empecher l'utilisateur d'écrire des caractères alphabétiques

Private Sub TextBox1_Change()  
On Error Resume Next  
    If Not IsNumeric(Right(TextBox1, 1)) And Right(TextBox1, 1) <> "," Then  
        MsgBox "Caractère invalide"  
        TextBox1 = Left(TextBox1, Len(TextBox1) - 1)  
    End If  
End Sub 

l

Private Sub TXT_Saisie_KeyUp(ByVal KeyCode As MSForms.ReturnInteger, ByVal Shift As Integer)
  If KeyCode = 20 Or (KeyCode >= 16 And KeyCode <= 18) Or KeyCode = 45 Or KeyCode = 91 Then Exit Sub
  If KeyCode < 48 Or KeyCode > 58 Then
    MsgBox ("erreur")
    If Len(Me.TXT_Saisie.Text) > 1 Then
      Me.TXT_Saisie.Text = Left(Me.TXT_Saisie.Text, Len(Me.TXT_Saisie.Text) - 1)
    Else
      Me.TXT_Saisie.Text = ""
    End If
  End If
End Sub

Private Sub TextBox1_Change()     
    Dim n As Double     
    On Error GoTo suite     
    n = CDbl("0" & TextBox1)     
    Exit Sub     
suite:     
    MsgBox "Caractère invalide"     
    TextBox1 = Left(TextBox1, Len(TextBox1) - 1)     
End Sub 

Private Sub TextBox1_Change() 
    Static TextBox1Sav As String 
    Dim n As Double 
    On Error GoTo suite 
    n = CDbl("0" & TextBox1) 
    On Error GoTo 0 
    TextBox1Sav = TextBox1 
    Exit Sub 
suite: 
    On Error GoTo 0 
    MsgBox "Caractère invalide" 
    TextBox1 = TextBox1Sav 
End Sub

if keyascii <48 or if keyascii > 58 then
keyascii = 0
beep
msgbox(" veuiller saisir des nombres , 
end if 

if keyascii =48  or keyascii =49 or keyascii = 50 or keyascii = 51 or keyascii = 52 or keyascii = 53 or keyascii = 54 or keyascii = 55 or keyascii = 56 or keyascii = 57 or keyascii = 58 or keyascii = 44 or keyascii = 44 then

else

beep 
keyascii = 0 
msgbox(" veuillez saisir un nombre")
end if