I found this code here long time ago:

   Private Sub Page_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load

        ' This causes the page to associate Enter key with cmdAddIt button click event.
        ' (source: Universal Thread Message ID: 814613, http://www.levelextreme.com)
        Page.RegisterHiddenField("__EVENTTARGET", "cmdAddIt")

    End Sub

Also, take a look at thread 849502


>Hi,
>
>I have a web form with a 2 buttons: CLOSE (btnClose) and SAVE (btnSave). I would like the ENTER key on the keyboard to fire the click event of the SAVE button. What property do I set to make the ENTER key the default. OR... do I need to include a method in an event handler.
>
>Regards,
>Neil