You need to listen on the beforeunload event. Here’s a kickoff example: window.onbeforeunload = function() { return “Hey, you’re leaving the site. Bye!”; }; This message will show up in kind of a confirmation dialogue. This message will show up right before the client unloads the page. That can be a browser close, but that … Read more
One of my favorite frameworks for doing this is Yahoo!’s Browser History Manager. You register events and it calls you back when the user returns Back to that state. And if you want to learn how it works, here’s a fun blog entry about the decisions Yahoo! made when designing it.
:first-child and :last-child, along with complimentary compatibility chart. :first-child is supported IE9 properly, and IE7 and IE8 sort of (see chart). :last-child is supported by IE9+ only. Both of them are supported well by the good browsers.
Yes they are different. View source shows you the original HTML source of the page. The inspector shows you the DOM as it was interpreted by the browser. This includes for example changes made by javascript which cannot be seen in the HTML source. Oh and this also counts for the developer tools that allow … Read more
Ctrl + Shift + J in firefox, if you don’t catch your mistakes until runtime. Of course firebug works better, but this is a quick way.
For those looking for a practical solution, see: How to find event listeners on a DOM node when debugging or from the JavaScript code? EventListenerList was in some old draft of DOM 3 Events and was long removed from the spec. As far as I know, at least Gecko still doesn’t have anything like this … Read more
Try with SVG filter. img { filter: blur(3px); -webkit-filter: blur(3px); -moz-filter: blur(3px); -o-filter: blur(3px); -ms-filter: blur(3px); filter: url(#blur); filter: progid:DXImageTransform.Microsoft.Blur(PixelRadius=”3″); } <img src=”https://i.stack.imgur.com/oURrw.png” /> <svg version=”1.1″ xmlns=”http://www.w3.org/2000/svg”> <filter id=”blur”> <feGaussianBlur stdDeviation=”3″ /> </filter> </svg>
That’s up to the user. You can’t force a user to open the browser in private browsing mode.
You could probably make that happen with something like PhantomJS You can write a phantomjs script that will load the page like a browser would, and then either take screenshots or use JS to inspect the page and pull out data.
If the types compared are the same, they are identical. That is to say they use the exact same algorithm. If the types are different, then performance is irrelevant. Either you need type coercion, or you don’t. If you don’t need it, don’t use == because the result you get may be unexpected.