Get the hashchange event to work in all browsers (including IE7)

• attachEvent requires events to be prefixed with on.
• You've different capitalizations for the method. Change hashchange in attachEvent tohashChange to get the event to work in IE8.
• Use the suggested implementation to support the hashchange implementation for IE7- and other old browsers.

I have created a cross-browser implementation, which adds the hashchange feature to browsers, even those who do not support it. The fallback is based on the specification.

//function hashchange  is assumed to exist. This function will fire on hashchangeif (!('onhashchange' in window)) {    var oldHref = location.href;    setInterval(function() {        var newHref = location.href;        if (oldHref !== newHref) {            var _oldHref = oldHref;            oldHref = newHref;            hashChange.call(window, {                'type': 'hashchange',                'newURL': newHref,                'oldURL': _oldHref            });        }    }, 100);} else if (window.addEventListener) {    window.addEventListener("hashchange", hashChange, false);}else if (window.attachEvent) {    window.attachEvent("onhashchange", hashChange);    }

Note: This code is useful for one hashchange event. If you want to add multiple hashchange handlers, use the following method.
It defines two functions, addHashChange and removeHashChange. Both methods take a function as an argument.

(function() {    if ('onhashchange' in window) {        if (window.addEventListener) {            window.addHashChange = function(func, before) {                window.addEventListener('hashchange', func, before);            };            window.removeHashChange = function(func) {                window.removeEventListener('hashchange', func);            };            return;        } else if (window.attachEvent) {            window.addHashChange = function(func) {                window.attachEvent('onhashchange', func);            };            window.removeHashChange = function(func) {                window.detachEvent('onhashchange', func);            };            return;        }    }    var hashChangeFuncs = [];    var oldHref = location.href;    window.addHashChange = function(func, before) {        if (typeof func === 'function')            hashChangeFuncs[before?'unshift':'push'](func);    };    window.removeHashChange = function(func) {        for (var i=hashChangeFuncs.length-1; i>=0; i--)            if (hashChangeFuncs[i] === func)                hashChangeFuncs.splice(i, 1);    };    setInterval(function() {        var newHref = location.href;        if (oldHref !== newHref) {            var _oldHref = oldHref;            oldHref = newHref;            for (var i=0; i<hashChangeFuncs.length; i++) {                hashChangeFuncs[i].call(window, {                    'type': 'hashchange',                    'newURL': newHref,                    'oldURL': _oldHref                });            }        }    }, 100);})();// Usage, infinitely many times:addHashChange(function(e){alert(e.newURL||location.href);});

attachEvent takes on two params:

bSuccess = object.attachEvent(sEvent, fpNotify)

[And is needed for all versions of IE below IE9! :( See MDN reference]

This could work:

if(window.addEventListener) {    window.addEventListener("hashchange", hashChange, false);}else if (window.attachEvent) {    window.attachEvent("onhashchange", hashchange);//SEE HERE...    //missed the on. Fixed thanks to @Robs answer.}

Of course if it is possible, you should just use JQuery, since it encapsulates all this for your.

And as always there is a plugin out there:http://benalman.com/projects/jquery-hashchange-plugin/