head：ok对a：js响应有效吗？

I have a list of items. A user can click a button to add new items. They can also delete existing items. Sometimes those items are saved and sometimes those items are unsaved. So if they are unsaved, I don't want to pass javascript back to browser to be executed. I just want to do nothing. So I figured to do this:I have a list of items. A user can click a butt