XL 2016 vba textbox interdire la saisie des 0 en premier

Private Sub TextBox1_KeyUp(ByVal KeyCode As MSForms.ReturnInteger, ByVal Shift As Integer)
If Len(TextBox1) = 1 And KeyCode = 96 Then TextBox1 = "": Exit Sub
If Len(TextBox1) > 1 Then _
If Not IsNumeric(Mid(TextBox1, Len(TextBox1) - 1, 1)) And KeyCode = 96 Then TextBox1 = Left(TextBox1, Len(TextBox1) - 1)
End Sub

Private Sub TextBox1_Change()
Dim t
t = " " & TextBox1
For i = 2 To Len(t)
    If Not IsNumeric(Mid(t, i - 1, 1)) And Mid(t, i, 1) = 0 Then
        t = Left(t, i - 1) & Mid(t, i + 1)
        i = i - 1
    End If
Next
TextBox1 = LTrim(t)
End Sub

Private Sub TextBox1_Change()
Dim t, i
t = " " & TextBox1
For i = 2 To Len(t)
    If Not IsNumeric(Mid(t, i - 1, 1)) And Mid(t, i, 1) = 0 Then
        t = Left(t, i - 1) & Mid(t, i + 1)
        i = i - 1
    End If
Next
TextBox1 = LTrim(t)
End Sub