onClosing
Introduced: PhantomJS 1.7
This callback is invoked when the WebPage object is being closed, either via page.close in the PhantomJS outer space or via window.close in the page’s client-side.
It is not invoked when child/descendant pages are being closed unless you also hook them up individually. It takes one argument, closingPage, which is a reference to the page that is closing. Once the onClosing handler has finished executing (returned), the WebPage object closingPage will become invalid.
Examples
var webPage = require('webpage');
var page = webPage.create();
page.onClosing = function(closingPage) {
console.log('The page is closing! URL: ' + closingPage.url);
};