Sending email to a user-entered email address

I would like to edit the XML so that when the user clicks on an Email Submit button, the form is sent to an email address that the user has entered into a form field. I have seen code like this on the click event

event.target.submitForm({cURL:"mailto:"+name@domain.com + ? subject=This form: " ,cSubmitAs:"XDP",cCharset:"utf-8"});

but can I edit the XML so that the form is sent to the email address set in one field of the form?