ActiveX TextBox

I have a problem with my macro that runs in UserForm and I would also like to apply it to sheet1 in textBox active controls. I have a question how to change the code to work in sheat1?

Option Explicit

Private Sub TextBox1_KeyPress(ByVal KeyAscii As MSForms.ReturnInteger)
   If Not IsNumeric(Chr(KeyAscii)) And Not KeyAscii = 8 Then
      KeyAscii = 0
   End If
End Sub

Private Sub TextBox1_Exit(ByVal Cancel As MSForms.ReturnBoolean)
If TextBox1.Value = "" Then
Exit Sub
End If
   If Val(TextBox1.Text) < 100 Or Val(TextBox1.Text) > 999 Then
      MsgBox "Error"
      Cancel = True
   End If
End Sub

Private Sub UserForm_Click()

End Sub