Action Form

I have a form with 3 combobox whitin a asp page called data.asp, whose
action form is itself; the first combobox drives the behaviour of the other
two.The onchange event of the first combobox is related to a javascript function
in which I call the submit method for the form, whose action form is itself.
This works fine.
The problem is that if I want to save the changes done by the user (clicking
the OK button) I need to set the action of the form to another page, for
example save.asp.
The question is: how to do this?
I had written a function inside the onclick method of the OK button that is
similar to the following one

document.MyForm.action = "save.asp";
document.MyForm.submit();