'Class1.cls
Private WithEvents txt As TextBox
Property Set TextBox(obj As Object)
Set txt=obj
End Property
Private Sub txt_Change()
if not IsNumeric(txt) then txt=""
End Sub
'Form1
Dim clstxt1 As New Class1
Private Sub Form_Load()
dim i as long
for i=0 to 1
set clstxt1.TextBox=Me.Text3(i)
next
End Sub