For Each Obj As Object in Me.Controls
  if TypeOf(Obj) is TextBox Then 
      AddHandler Ctype(Obj, TextBox).TextChanged, AddressOf MyText_Changed 
  endif
Next  
 
Sub MyText_Changed (sender as Object , e as Eventargs) ' hier kein Handle 
' setzen !!!
   If sender is me.TextBox1 then
   ' Code f. Txt 1
   elseIf sender is me.TextBox2 then
   ' Code f. Txt 2
   elseIf sender is me.TextBox1 then
   ' Code f. Txt 3
   endif 
  ' ... usw..
End Sub