Detecting Browser History Actions

I am building a Html 5 website using push state and I wondering whether its possible in javascript or JQuery to detect whether the browser’s back button has been pushed. I would like to include it in an if statement like so:

if (back_btn clicked){
//do stuff
}
if (forward_btn clicked){

}

Answer

You’re looking for the popstate event.

An example:

window.onpopstate = function(event) {
    alert("location: " + document.location);
}

Or with the ever-popular jQuery:

$(window).on('popstate',function(event) {
    alert("location: " + document.location);
});

This fires whenever history is accessed, such as back/forward. A quick note, in Chrome this also fires on the page load, so a quick way around is to check if the event is null.

if(event.originalEvent.state!=null){
    // do something
}

Another good resource is the History.js jQuery plugin, which has a fallback using hashtags and such. It also makes detection of popstate events very straightforward.