Question : New record, if field is empty, msgbox

Experts,

If I am on a form and the record is new and txtType is blank and someone trys to close form, I need a msgbox that says "Enter Type" and then cancels the close of the form.  

Thank you.

Answer : New record, if field is empty, msgbox

do this in the beforeupdate evnt of the form

private sub form_BeforeUpdate(cancel as integer)
if len(me.txtType & "")=0 then
   msgbox "Enter Type"
   me.txtType.setfocus
   cancel=true
   exit sub
end if


end sub