Develop Reference

How does one prevent the opening of a new tab or window when hyperlink behavior was created virtually by e.g. an HTML button's "click" event handling?

I can disable opening new tab or window in case of <a> tag by removing target attribute e.g. target='_blank'
In some cases instead of <a> website put <button> and add onClick() or submit() etc which programmatically generates a link and sets the target attribute.
<button id="653cde4c-1620-11ec-85b5-5ae26c154b46">
<div>click here</div>
</button>
In some webpack generated javascript file there would be something like which would not be easy to find and read minified code.
var button = document.querySelctor('653cde4c-1620-11ec-85b5-5ae26c154b46')
// Add whatever you want to add to this button element, e.g. add onClick() or submit() or something else which I am not sure of
We can see image at https://i.stack.imgur.com/8oG5w.png
In such case where <button> is providing link click functionality. I can not view and edit onClick() or submit() etc as its webpack generated javascript. I can only run my javascript code after loading of that webapge in devtools console.
How can I disable opening new tab or new window of browser in such case? Or What javascript code should I run to override <button> link behaviour?

Depending on how the webpack based code does manage the tab handling of resources one possible solution was to wrap own code around window.open or even entirely replace it with an own implementation.
As for the wrapping, based on the intercepted data, one could decide of whether one does suppress the url-handling entirely or, instead of opening a new tab/window, does a forwarding to location.href or even proceed with invoking the original window.open.
// untouchable 3rd party code
//
function alienLocationHandler({ currentTarget }) {
let { url, target } = currentTarget.dataset;
url = (url ?? '').trim();
if (url) {
target = (target ?? '').trim();
if (target) {
// due to SO's permission handling ...
//
// ... Blocked opening 'https://stackoverflow.com/' in a
// new window because the request was made in a sandboxed
// frame whose 'allow-popups' permission is not set.
//
window.open(url, target);
} else {
window.location.href = url;
}
}
}
document
.querySelectorAll('[data-url]')
.forEach(elmNode =>
elmNode.addEventListener('click', alienLocationHandler)
);
// one possible approach :: wrap around `window.open`
//
window.open = (function createAroundHandler(proceed, thisArg) {
return function aroundWindowOpen(url, target, ...rest) {
console.log('aroundWindowOpen ...', {
url,
target,
rest,
});
// - of cause all the code is just for demonstration purpose.
//
// - the OP has to come up with own handler logic which does
// fit the OP's needs best.
if (url !== 'https://stackoverflow.com') {
// invocation of the original `window.open`
// will be blocked by SO's permission handling.
proceed.call(thisArg, url, target, ...rest);
} else {
// delayed fowarding to `location.href`.
setTimeout(() => { window.location.href = url }, 5000);
}
};
}(window.open, window));
body { margin: 0; }
.as-console-wrapper { min-height: 87%; top: auto; }
<button data-url="https://stackoverflow.com">
no interception
</button>
<button
data-url="https://google.com"
data-target='google'
>
intercepted & open attempt
</button>
<button
id="_653cde4c-1620-11ec-85b5-5ae26c154b46"
data-url="https://stackoverflow.com"
data-target='_blank'
>
intercepted and forwarded with 5sec delay
</button>
Another approach was to make use of event delegation by listening to and handling click events at e.g. document.body level.
// untouchable 3rd party code
//
function alienLocationHandler({ currentTarget }) {
let { url, target } = currentTarget.dataset;
url = (url ?? '').trim();
if (url) {
target = (target ?? '').trim();
if (target) {
// due to SO's permission handling ...
//
// ... Blocked opening 'https://stackoverflow.com/' in a
// new window because the request was made in a sandboxed
// frame whose 'allow-popups' permission is not set.
//
window.open(url, target);
} else {
window.location.href = url;
}
}
}
document
.querySelectorAll('[data-url]')
.forEach(elmNode =>
elmNode.addEventListener('click', alienLocationHandler)
);
// another possible approach :: event delegation
//
// - [https://developer.mozilla.org/en-US/docs/Learn/JavaScript/Building_blocks/Events#event_delegation]
// - [https://davidwalsh.name/event-delegate]
//
// - [https://javascript.info/event-delegation]
// - [https://learn.jquery.com/events/event-delegation/]
//
function isButtonEvent(activeElement, targetNode) {
return (activeElement.tagName.toLowerCase() === 'button') && (
activeElement.isSameNode(targetNode) ||
activeElement.contains(targetNode)
);
}
function preventSpecificButtonClickBehavior(evt) {
const elmButton = document.activeElement;
if (isButtonEvent(elmButton, evt.target)) {
const url = (elmButton.dataset.url ?? '').trim();
const isUrlBasedPrevented = (url !== 'https://stackoverflow.com');
const isIdBasedPrevented = ((elmButton.id ?? '').trim() !== '');
if (isUrlBasedPrevented || isIdBasedPrevented) {
evt.stopImmediatePropagation();
evt.stopPropagation();
if (isUrlBasedPrevented) {
console.log('prevented button click behavior ... URL based')
}
if (isIdBasedPrevented) {
console.log('prevented button click behavior ... ID based')
}
}
}
}
document
.body
.addEventListener(
'click',
preventSpecificButtonClickBehavior,
// - [https://developer.mozilla.org/en-US/docs/Web/API/EventTarget/addEventListener#parameters]
// - The boolean `useCapture` parameter/flag does the trick if set as `true` value.
true
);
body { margin: 0; }
.as-console-wrapper { min-height: 87%; top: auto; }
<button data-url="https://stackoverflow.com">
click behavior not prevented
</button>
<button
id="_653cde4c-1620-11ec-85b5-5ae26c154b46"
data-url="https://stackoverflow.com"
>
prevented behavior (id based)
</button>
<button
data-url="https://google.com"
data-target='google'
>
<span>
<span>
prevented behavior (url based)
</span>
</span>
</button>

Probably the logic in the onClick() does something like window.open(url, [params]). You can change this to setting window.location.href = url; and the url will be loaded in the same window.

History.pushState creates large amout of entries

I'm trying to create something like a dynamic page, but I have this problem. When I fire history.pushState it creates large amount of history entries, even though the action that fires it is run only once. My code is as follows:
var url = 'http://localhost:8888/depeche-mode/violator'; // example url
var plainUrl = url + '/?plain',
startUrl = 'http://localhost:8888/',
newUrl = url.replace(startUrl, '#/');
$('#content').animate({
opacity: 0
}, 250, function() {
$('#content').load(plainUrl +' #content > *', function(response) {
$('#content').animate({opacity:1}, 250, function() {
document.title = pageTitle;
Posts.historyHash(newUrl);
});
});
});
edit:
var Posts = {
historyHash: function(newUrl) {
window.location.hash = newUrl;
$(window).bind('hashchange', function() {
var url = window.location.hash,
nohash = url.replace('#',''),
properUrl = 'http://localhost:8888/'+nohash;
history.pushState('','',newUrl);
});
}
}
The problem is very serious when I want to use Back button in my browser - I need to click it couple of times before I actually get to change the url. What can I do?

You're calling historyHash when you load content, and historyHash registers an event handler on window — every time you call it. So you end up with a bunch of event handlers for the hashchange event.
You presumably only want one. Either just register one, or unregister the previous ones when registering a new one.
I can't quite tell which of those you want, but as the handler uses the newUrl, it may well be that you want to unregister previous handlers. If so, probably best to use an event namespace so you only unregister your own handlers:
var Posts = {
historyHash: function(newUrl) {
window.location.hash = newUrl;
$(window)
.unbind('hashchange.historyhash') // Out with the old
.bind('hashchange.historyhash', function() { // In with the new
var url = window.location.hash,
nohash = url.replace('#',''),
properUrl = 'http://localhost:8888/'+nohash;
history.pushState('','',newUrl);
});
}
}
Although looking at it, you could just use a single handler and remember newUrl on Posts:
var Posts = {
historyHash: function(newUrl) {
window.location.hash = newUrl;
this.newUrl = newUrl;
}
};
$(window).bind('hashchange', function() {
var url, nohash, properUrl;
if (Posts.newUrl) {
url = window.location.hash,
nohash = url.replace('#',''),
properUrl = 'http://localhost:8888/'+nohash;
history.pushState('','',Posts.newUrl);
}
});

How to Detect Browser Back Button event - Cross Browser

How do you definitively detect whether or not the user has pressed the back button in the browser?
How do you enforce the use of an in-page back button inside a single page web application using a #URL system?
Why on earth don't browser back buttons fire their own events!?

(Note: As per Sharky's feedback, I've included code to detect backspaces)
So, I've seen these questions frequently on SO, and have recently run into the issue of controlling back button functionality myself. After a few days of searching for the best solution for my application (Single-Page with Hash Navigation), I've come up with a simple, cross-browser, library-less system for detecting the back button.
Most people recommend using:
window.onhashchange = function() {
//blah blah blah
}
However, this function will also be called when a user uses on in-page element that changes the location hash. Not the best user experience when your user clicks and the page goes backwards or forwards.
To give you a general outline of my system, I'm filling up an array with previous hashes as my user moves through the interface. It looks something like this:
function updateHistory(curr) {
window.location.lasthash.push(window.location.hash);
window.location.hash = curr;
}
Pretty straight forward. I do this to ensure cross-browser support, as well as support for older browsers. Simply pass the new hash to the function, and it'll store it for you and then change the hash (which is then put into the browser's history).
I also utilise an in-page back button that moves the user between pages using the lasthash array. It looks like this:
function goBack() {
window.location.hash = window.location.lasthash[window.location.lasthash.length-1];
//blah blah blah
window.location.lasthash.pop();
}
So this will move the user back to the last hash, and remove that last hash from the array (I have no forward button right now).
So. How do I detect whether or not a user has used my in-page back button, or the browser button?
At first I looked at window.onbeforeunload, but to no avail - that is only called if the user is going to change pages. This does not happen in a single-page-application using hash navigation.
So, after some more digging, I saw recommendations for trying to set a flag variable. The issue with this in my case, is that I would try to set it, but as everything is asynchronous, it wouldn't always be set in time for the if statement in the hash change. .onMouseDown wasn't always called in click, and adding it to an onclick wouldn't ever trigger it fast enough.
This is when I started to look at the difference between document, and window. My final solution was to set the flag using document.onmouseover, and disable it using document.onmouseleave.
What happens is that while the user's mouse is inside the document area (read: the rendered page, but excluding the browser frame), my boolean is set to true. As soon as the mouse leaves the document area, the boolean flips to false.
This way, I can change my window.onhashchange to:
window.onhashchange = function() {
if (window.innerDocClick) {
window.innerDocClick = false;
} else {
if (window.location.hash != '#undefined') {
goBack();
} else {
history.pushState("", document.title, window.location.pathname);
location.reload();
}
}
}
You'll note the check for #undefined. This is because if there is no history available in my array, it returns undefined. I use this to ask the user if they want to leave using a window.onbeforeunload event.
So, in short, and for people that aren't necessarily using an in-page back button or an array to store the history:
document.onmouseover = function() {
//User's mouse is inside the page.
window.innerDocClick = true;
}
document.onmouseleave = function() {
//User's mouse has left the page.
window.innerDocClick = false;
}
window.onhashchange = function() {
if (window.innerDocClick) {
//Your own in-page mechanism triggered the hash change
} else {
//Browser back button was clicked
}
}
And there you have it. a simple, three-part way to detect back button usage vs in-page elements with regards to hash navigation.
EDIT:
To ensure that the user doesn't use backspace to trigger the back event, you can also include the following (Thanks to #thetoolman on this Question):
$(function(){
/*
* this swallows backspace keys on any non-input element.
* stops backspace -> back
*/
var rx = /INPUT|SELECT|TEXTAREA/i;
$(document).bind("keydown keypress", function(e){
if( e.which == 8 ){ // 8 == backspace
if(!rx.test(e.target.tagName) || e.target.disabled || e.target.readOnly ){
e.preventDefault();
}
}
});
});

You can try popstate event handler, e.g:
window.addEventListener('popstate', function(event) {
// The popstate event is fired each time when the current history entry changes.
var r = confirm("You pressed a Back button! Are you sure?!");
if (r == true) {
// Call Back button programmatically as per user confirmation.
history.back();
// Uncomment below line to redirect to the previous page instead.
// window.location = document.referrer // Note: IE11 is not supporting this.
} else {
// Stay on the current page.
history.pushState(null, null, window.location.pathname);
}
history.pushState(null, null, window.location.pathname);
}, false);
Note: For the best results, you should load this code only on specific pages where you want to implement the logic to avoid any other unexpected issues.
The popstate event is fired each time when the current history entry changes (user navigates to a new state). That happens when user clicks on browser's Back/Forward buttons or when history.back(), history.forward(), history.go() methods are programatically called.
The event.state is property of the event is equal to the history state object.
For jQuery syntax, wrap it around (to add even listener after document is ready):
(function($) {
// Above code here.
})(jQuery);
See also: window.onpopstate on page load
See also the examples on Single-Page Apps and HTML5 pushState page:
<script>
// jQuery
$(window).on('popstate', function (e) {
var state = e.originalEvent.state;
if (state !== null) {
//load content with ajax
}
});
// Vanilla javascript
window.addEventListener('popstate', function (e) {
var state = e.state;
if (state !== null) {
//load content with ajax
}
});
</script>
This should be compatible with Chrome 5+, Firefox 4+, IE 10+, Safari 6+, Opera 11.5+ and similar.

if (window.performance && window.performance.navigation.type == window.performance.navigation.TYPE_BACK_FORWARD) {
alert('hello world');
}
This is the only one solution that worked for me (it's not a onepage website).
It's working with Chrome, Firefox and Safari.

I had been struggling with this requirement for quite a while and took some of the solutions above to implement it. However, I stumbled upon an observation and it seems to work across Chrome, Firefox and Safari browsers + Android and iPhone
On page load:
window.history.pushState({page: 1}, "", "");
window.onpopstate = function(event) {
// "event" object seems to contain value only when the back button is clicked
// and if the pop state event fires due to clicks on a button
// or a link it comes up as "undefined"
if(event){
// Code to handle back button or prevent from navigation
}
else{
// Continue user action through link or button
}
}
Let me know if this helps. If am missing something, I will be happy to understand.

In javascript, navigation type 2 means browser's back or forward button clicked and the browser is actually taking content from cache.
if(performance.navigation.type == 2)
{
//Do your code here
}

Correct answer is already there to answer the question. I want to mention new JavaScript API PerformanceNavigationTiming, it's replacing deprecated performance.navigation.
Following code will log in console "back_forward" if user landed on your page using back or forward button. Take a look at compatibility table before using it in your project.
var perfEntries = performance.getEntriesByType("navigation");
for (var i = 0; i < perfEntries.length; i++) {
console.log(perfEntries[i].type);
}

This will definitely work (For detecting back button click)
$(window).on('popstate', function(event) {
alert("pop");
});

My variant:
const inFromBack = performance && performance.getEntriesByType( 'navigation' ).map( nav => nav.type ).includes( 'back_forward' )

Browser: https://jsfiddle.net/Limitlessisa/axt1Lqoz/
For mobile control: https://jsfiddle.net/Limitlessisa/axt1Lqoz/show/
$(document).ready(function() {
$('body').on('click touch', '#share', function(e) {
$('.share').fadeIn();
});
});
// geri butonunu yakalama
window.onhashchange = function(e) {
var oldURL = e.oldURL.split('#')[1];
var newURL = e.newURL.split('#')[1];
if (oldURL == 'share') {
$('.share').fadeOut();
e.preventDefault();
return false;
}
//console.log('old:'+oldURL+' new:'+newURL);
}
.share{position:fixed; display:none; top:0; left:0; width:100%; height:100%; background:rgba(0,0,0,.8); color:white; padding:20px;
<!DOCTYPE html>
<html>
<head>
<title>Back Button Example</title>
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
</head>
<body style="text-align:center; padding:0;">
Share
<div class="share" style="">
<h1>Test Page</h1>
<p> Back button press please for control.</p>
</div>
</body>
</html>

See this:
history.pushState(null, null, location.href);
window.onpopstate = function () {
history.go(1);
};
it works fine...

I was able to use some of the answers in this thread and others to get it working in IE and Chrome/Edge. history.pushState for me wasn't supported in IE11.
if (history.pushState) {
//Chrome and modern browsers
history.pushState(null, document.title, location.href);
window.addEventListener('popstate', function (event) {
history.pushState(null, document.title, location.href);
});
}
else {
//IE
history.forward();
}

A full-fledged component can be implemented only if you redefine the API (change the methods of object ' history ')
I will share the class just written.
Tested on Chrome and Mozilla
Support only HTML5 and ECMAScript5-6
class HistoryNavigation {
static init()
{
if(HistoryNavigation.is_init===true){
return;
}
HistoryNavigation.is_init=true;
let history_stack=[];
let n=0;
let current_state={timestamp:Date.now()+n};
n++;
let init_HNState;
if(history.state!==null){
current_state=history.state.HNState;
history_stack=history.state.HNState.history_stack;
init_HNState=history.state.HNState;
} else {
init_HNState={timestamp:current_state.timestamp,history_stack};
}
let listenerPushState=function(params){
params=Object.assign({state:null},params);
params.state=params.state!==null?Object.assign({},params.state):{};
let h_state={ timestamp:Date.now()+n};
n++;
let key = history_stack.indexOf(current_state.timestamp);
key=key+1;
history_stack.splice(key);
history_stack.push(h_state.timestamp);
h_state.history_stack=history_stack;
params.state.HNState=h_state;
current_state=h_state;
return params;
};
let listenerReplaceState=function(params){
params=Object.assign({state:null},params);
params.state=params.state!==null?Object.assign({},params.state):null;
let h_state=Object.assign({},current_state);
h_state.history_stack=history_stack;
params.state.HNState=h_state;
return params;
};
let desc=Object.getOwnPropertyDescriptors(History.prototype);
delete desc.constructor;
Object.defineProperties(History.prototype,{
replaceState:Object.assign({},desc.replaceState,{
value:function(state,title,url){
let params={state,title,url};
HistoryNavigation.dispatchEvent('history.state.replace',params);
params=Object.assign({state,title,url},params);
params=listenerReplaceState(params);
desc.replaceState.value.call(this,params.state,params.title,params.url);
}
}),
pushState:Object.assign({},desc.pushState,{
value:function(state,title,url){
let params={state,title,url};
HistoryNavigation.dispatchEvent('history.state.push',params);
params=Object.assign({state,title,url},params);
params=listenerPushState(params);
return desc.pushState.value.call(this, params.state, params.title, params.url);
}
})
});
HistoryNavigation.addEventListener('popstate',function(event){
let HNState;
if(event.state==null){
HNState=init_HNState;
} else {
HNState=event.state.HNState;
}
let key_prev=history_stack.indexOf(current_state.timestamp);
let key_state=history_stack.indexOf(HNState.timestamp);
let delta=key_state-key_prev;
let params={delta,event,state:Object.assign({},event.state)};
delete params.state.HNState;
HNState.history_stack=history_stack;
if(event.state!==null){
event.state.HNState=HNState;
}
current_state=HNState;
HistoryNavigation.dispatchEvent('history.go',params);
});
}
static addEventListener(...arg)
{
window.addEventListener(...arg);
}
static removeEventListener(...arg)
{
window.removeEventListener(...arg);
}
static dispatchEvent(event,params)
{
if(!(event instanceof Event)){
event=new Event(event,{cancelable:true});
}
event.params=params;
window.dispatchEvent(event);
};
}
HistoryNavigation.init();
// exemple
HistoryNavigation.addEventListener('popstate',function(event){
console.log('Will not start because they blocked the work');
});
HistoryNavigation.addEventListener('history.go',function(event){
event.params.event.stopImmediatePropagation();// blocked popstate listeners
console.log(event.params);
// back or forward - see event.params.delta
});
HistoryNavigation.addEventListener('history.state.push',function(event){
console.log(event);
});
HistoryNavigation.addEventListener('history.state.replace',function(event){
console.log(event);
});
history.pushState({h:'hello'},'','');
history.pushState({h:'hello2'},'','');
history.pushState({h:'hello3'},'','');
history.back();
```

Here's my take at it. The assumption is, when the URL changes but there has no click within the document detected, it's a browser back (yes, or forward). A users click is reset after 2 seconds to make this work on pages that load content via Ajax:
(function(window, $) {
var anyClick, consoleLog, debug, delay;
delay = function(sec, func) {
return setTimeout(func, sec * 1000);
};
debug = true;
anyClick = false;
consoleLog = function(type, message) {
if (debug) {
return console[type](message);
}
};
$(window.document).click(function() {
anyClick = true;
consoleLog("info", "clicked");
return delay(2, function() {
consoleLog("info", "reset click state");
return anyClick = false;
});
});
return window.addEventListener("popstate", function(e) {
if (anyClick !== true) {
consoleLog("info", "Back clicked");
return window.dataLayer.push({
event: 'analyticsEvent',
eventCategory: 'test',
eventAction: 'test'
});
}
});
})(window, jQuery);

The document.mouseover does not work for IE and FireFox.
However I have tried this :
$(document).ready(function () {
setInterval(function () {
var $sample = $("body");
if ($sample.is(":hover")) {
window.innerDocClick = true;
} else {
window.innerDocClick = false;
}
});
});
window.onhashchange = function () {
if (window.innerDocClick) {
//Your own in-page mechanism triggered the hash change
} else {
//Browser back or forward button was pressed
}
};
This works for Chrome and IE and not FireFox. Still working to get FireFox right. Any easy way on detecting Browser back/forward button click are welcome, not particularly in JQuery but also AngularJS or plain Javascript.

I solved it by keeping track of the original event that triggered the hashchange (be it a swipe, a click or a wheel), so that the event wouldn't be mistaken for a simple landing-on-page, and using an additional flag in each of my event bindings. The browser won't set the flag again to false when hitting the back button:
var evt = null,
canGoBackToThePast = true;
$('#next-slide').on('click touch', function(e) {
evt = e;
canGobackToThePast = false;
// your logic (remember to set the 'canGoBackToThePast' flag back to 'true' at the end of it)
}

<input style="display:none" id="__pageLoaded" value=""/>
$(document).ready(function () {
if ($("#__pageLoaded").val() != 1) {
$("#__pageLoaded").val(1);
} else {
shared.isBackLoad = true;
$("#__pageLoaded").val(1);
// Call any function that handles your back event
}
});
The above code worked for me. On mobile browsers, when the user clicked on the back button, we wanted to restore the page state as per his previous visit.

Solution for Kotlin/JS (React):
import org.w3c.dom.events.Event
import kotlin.browser.document
import kotlin.browser.window
...
override fun componentDidMount() {
window.history.pushState(null, document.title, window.location.href)
window.addEventListener("popstate", actionHandler)
}
...
val actionHandler: (Event?) -> Unit = {
window.history.pushState(
null,
document.title,
window.location.href
)
// add your actions here
}

Was looking for a solution for this issue and put together a simple skeleton test html based on a few answers here and the MDN Web Doc pages for History.pushState() and WindowEventHandlers.onpopstate.
The following HTML and JavaScript is easy enough to copy and paste and test.
Works with back and forward browser buttons, shortcut keys, adds a change to the URL (which is important in some cases).
Simply enough to add to existing code key points and should be expandable too.
<html>
<body>
<div id="p1">Option 1</div>
<div id="p2">Option 2</div>
<div id="p3">Option 3</div>
<div id="p4">Option 4</div>
<div id="c"></div>
<script>
var chg={
set:function(str){
var d=document.getElementById("c");
d.textContent=str;
},
go:function(e){
var s={"p":this.id};
chg.set(s.p);
hstry.add(s);
}
};
var hstry={
add:function(s){
var u=new URL(window.location);
u.searchParams.set("x",s.p);
window.history.pushState(s,"",u);
},
adjust:function(state){
if(state.p){
chg.set(state.p);
}
}
};
window.onpopstate=function(e){
console.log("popstate, e.state:["+ JSON.stringify(e.state) +"]");
hstry.adjust(e.state);
}
window.onload=function(){
var i,d,a=["p1","p2","p3","p4"];
for(i=0;i<a.length;i++){
d=document.getElementById(a[i]);
d.addEventListener("click",chg.go,false);
}
}
</script>
</body>
</html>

browser will emit popstate event if you navigate through your app with calling
window.history.pushState({},'','/to')
If you manually enter the addresses into the address bar and click on the back button, popstate event will NOT be fired.
If you navigate in your app with this simplified function
const navigate = (to) => {
window.history.pushState({}, ",", to);
};
then this will work
const handlePopstate = () => {
console.log("popped");
};
window.addEventListener("popstate", handlePopstate);

I tried the above options but none of them is working for me. Here is the solution
if(window.event)
{
if(window.event.clientX < 40 && window.event.clientY < 0)
{
alert("Browser back button is clicked...");
}
else
{
alert("Browser refresh button is clicked...");
}
}
Refer this link http://www.codeproject.com/Articles/696526/Solution-to-Browser-Back-Button-Click-Event-Handli for more details

JavaScript or jQuery browser back button click detector

Could someone please share experience / code how we can detect the browser back button click (for any type of browsers)?
We need to cater all browser that doesn't support HTML5

The 'popstate' event only works when you push something before. So you have to do something like this:
jQuery(document).ready(function($) {
if (window.history && window.history.pushState) {
window.history.pushState('forward', null, './#forward');
$(window).on('popstate', function() {
alert('Back button was pressed.');
});
}
});
For browser backward compatibility I recommend: history.js

In javascript, navigation type 2 means browser's back or forward button clicked and the browser is actually taking content from cache.
if(performance.navigation.type == 2) {
//Do your code here
}

there are a lot of ways how you can detect if user has clicked on the Back button. But everything depends on what your needs. Try to explore links below, they should help you.
Detect if user pressed "Back" button on current page:
Is there a way using Jquery to detect the back button being pressed cross browsers
detect back button click in browser
Detect if current page is visited after pressing "Back" button on previous("Forward") page:
Is there a cross-browser onload event when clicking the back button?
trigger event on browser back button click

Found this to work well cross browser and mobile back_button_override.js .
(Added a timer for safari 5.0)
// managage back button click (and backspace)
var count = 0; // needed for safari
window.onload = function () {
if (typeof history.pushState === "function") {
history.pushState("back", null, null);
window.onpopstate = function () {
history.pushState('back', null, null);
if(count == 1){window.location = 'your url';}
};
}
}
setTimeout(function(){count = 1;},200);

In case of HTML5 this will do the trick
window.onpopstate = function() {
alert("clicked back button");
}; history.pushState({}, '');

You can use this awesome plugin
https://github.com/ianrogren/jquery-backDetect
All you need to do is to write this code
$(window).load(function(){
$('body').backDetect(function(){
// Callback function
alert("Look forward to the future, not the past!");
});
});
Best

In my case I am using jQuery .load() to update DIVs in a SPA (single page [web] app) .
Being new to working with $(window).on('hashchange', ..) event listener , this one proved challenging and took a bit to hack on. Thanks to reading a lot of answers and trying different variations, finally figured out how to make it work in the following manner. Far as I can tell, it is looking stable so far.
In summary - there is the variable globalCurrentHash that should be set each time you load a view.
Then when $(window).on('hashchange', ..) event listener runs, it checks the following:
If location.hash has the same value, it means Going Forward
If location.hash has different value, it means Going Back
I realize using global vars isn't the most elegant solution, but doing things OO in JS seems tricky to me so far. Suggestions for improvement/refinement certainly appreciated
Set Up:
Define a global var :
var globalCurrentHash = null;
When calling .load() to update the DIV, update the global var as well :
function loadMenuSelection(hrefVal) {
$('#layout_main').load(nextView);
globalCurrentHash = hrefVal;
}
On page ready, set up the listener to check the global var to see if Back Button is being pressed:
$(document).ready(function(){
$(window).on('hashchange', function(){
console.log( 'location.hash: ' + location.hash );
console.log( 'globalCurrentHash: ' + globalCurrentHash );
if (location.hash == globalCurrentHash) {
console.log( 'Going fwd' );
}
else {
console.log( 'Going Back' );
loadMenuSelection(location.hash);
}
});
});

It's available in the HTML5 History API. The event is called 'popstate'

Disable the url button by following function
window.onload = function () {
if (typeof history.pushState === "function") {
history.pushState("jibberish", null, null);
window.onpopstate = function () {
history.pushState('newjibberish', null, null);
// Handle the back (or forward) buttons here
// Will NOT handle refresh, use onbeforeunload for this.
};
}
else {
var ignoreHashChange = true;
window.onhashchange = function () {
if (!ignoreHashChange) {
ignoreHashChange = true;
window.location.hash = Math.random();
// Detect and redirect change here
// Works in older FF and IE9
// * it does mess with your hash symbol (anchor?) pound sign
// delimiter on the end of the URL
}
else {
ignoreHashChange = false;
}
};
}
};

Hasan Badshah's answer worked for me, but the method is slated to be deprecated and may be problematic for others going forward. Following the MDN web docs on alternative methods, I landed here: PerformanceNavigationTiming.type
if (performance.getEntriesByType("navigation")[0].type === 'back_forward') {
// back or forward button functionality
}
This doesn't directly solve for back button over the forward button, but was good enough for what I needed. In the docs they detail the available event data that may be helpful with solving your specific needs:
function print_nav_timing_data() {
// Use getEntriesByType() to just get the "navigation" events
var perfEntries = performance.getEntriesByType("navigation");
for (var i=0; i < perfEntries.length; i++) {
console.log("= Navigation entry[" + i + "]");
var p = perfEntries[i];
// dom Properties
console.log("DOM content loaded = " + (p.domContentLoadedEventEnd -
p.domContentLoadedEventStart));
console.log("DOM complete = " + p.domComplete);
console.log("DOM interactive = " + p.interactive);
// document load and unload time
console.log("document load = " + (p.loadEventEnd - p.loadEventStart));
console.log("document unload = " + (p.unloadEventEnd -
p.unloadEventStart));
// other properties
console.log("type = " + p.type);
console.log("redirectCount = " + p.redirectCount);
}
}
According to the Docs at the time of this post it is still in a working draft state and is not supported in IE or Safari, but that may change by the time it is finished. Check the Docs for updates.

suppose you have a button:
<button onclick="backBtn();">Back...</button>
Here the code of the backBtn method:
function backBtn(){
parent.history.back();
return false;
}

How to detect if URL has changed after hash in JavaScript

How can I check if a URL has changed in JavaScript? For example, websites like GitHub, which use AJAX, will append page information after a # symbol to create a unique URL without reloading the page. What is the best way to detect if this URL changes?
Is the onload event called again?
Is there an event handler for the URL?
Or must the URL be checked every second to detect a change?

I wanted to be able to add locationchange event listeners. After the modification below, we'll be able to do it, like this
window.addEventListener('locationchange', function () {
console.log('location changed!');
});
In contrast, window.addEventListener('hashchange',() => {}) would only fire if the part after a hashtag in a url changes, and window.addEventListener('popstate',() => {}) doesn't always work.
This modification, similar to Christian's answer, modifies the history object to add some functionality.
By default, before these modifications, there's a popstate event, but there are no events for pushstate, and replacestate.
This modifies these three functions so that all fire a custom locationchange event for you to use, and also pushstate and replacestate events if you want to use those.
These are the modifications:
(() => {
let oldPushState = history.pushState;
history.pushState = function pushState() {
let ret = oldPushState.apply(this, arguments);
window.dispatchEvent(new Event('pushstate'));
window.dispatchEvent(new Event('locationchange'));
return ret;
};
let oldReplaceState = history.replaceState;
history.replaceState = function replaceState() {
let ret = oldReplaceState.apply(this, arguments);
window.dispatchEvent(new Event('replacestate'));
window.dispatchEvent(new Event('locationchange'));
return ret;
};
window.addEventListener('popstate', () => {
window.dispatchEvent(new Event('locationchange'));
});
})();
Note, we're creating a closure, to save the old function as part of the new one, so that it gets called whenever the new one is called.

In modern browsers (IE8+, FF3.6+, Chrome), you can just listen to the hashchange event on window.
In some old browsers, you need a timer that continually checks location.hash. If you're using jQuery, there is a plugin that does exactly that.
Example
Below I undo any URL change, to keep just the scrolling:
<script type="text/javascript">
if (window.history) {
var myOldUrl = window.location.href;
window.addEventListener('hashchange', function(){
window.history.pushState({}, null, myOldUrl);
});
}
</script>
Note that above used history-API is available in Chrome, Safari, Firefox 4+, and Internet Explorer 10pp4+

window.onhashchange = function() {
//code
}
window.onpopstate = function() {
//code
}
or
window.addEventListener('hashchange', function() {
//code
});
window.addEventListener('popstate', function() {
//code
});
with jQuery
$(window).bind('hashchange', function() {
//code
});
$(window).bind('popstate', function() {
//code
});

EDIT after a bit of researching:
It somehow seems that I have been fooled by the documentation present on Mozilla docs. The popstate event (and its callback function onpopstate) are not triggered whenever the pushState() or replaceState() are called in code. Therefore the original answer does not apply in all cases.
However there is a way to circumvent this by monkey-patching the functions according to #alpha123:
var pushState = history.pushState;
history.pushState = function () {
pushState.apply(history, arguments);
fireEvents('pushState', arguments); // Some event-handling function
};
Original answer
Given that the title of this question is "How to detect URL change" the answer, when you want to know when the full path changes (and not just the hash anchor), is that you can listen for the popstate event:
window.onpopstate = function(event) {
console.log("location: " + document.location + ", state: " + JSON.stringify(event.state));
};
Reference for popstate in Mozilla Docs
Currently (Jan 2017) there is support for popstate from 92% of browsers worldwide.

With jquery (and a plug-in) you can do
$(window).bind('hashchange', function() {
/* things */
});
http://benalman.com/projects/jquery-hashchange-plugin/
Otherwise yes, you would have to use setInterval and check for a change in the hash event (window.location.hash)
Update! A simple draft
function hashHandler(){
this.oldHash = window.location.hash;
this.Check;
var that = this;
var detect = function(){
if(that.oldHash!=window.location.hash){
alert("HASH CHANGED - new has" + window.location.hash);
that.oldHash = window.location.hash;
}
};
this.Check = setInterval(function(){ detect() }, 100);
}
var hashDetection = new hashHandler();

Add a hash change event listener!
window.addEventListener('hashchange', function(e){console.log('hash changed')});
Or, to listen to all URL changes:
window.addEventListener('popstate', function(e){console.log('url changed')});
This is better than something like the code below because only one thing can exist in window.onhashchange and you'll possibly be overwriting someone else's code.
// Bad code example
window.onhashchange = function() {
// Code that overwrites whatever was previously in window.onhashchange
}

this solution worked for me:
function checkURLchange(){
if(window.location.href != oldURL){
alert("url changed!");
oldURL = window.location.href;
}
}
var oldURL = window.location.href;
setInterval(checkURLchange, 1000);

None of these seem to work when a link is clicked that which redirects you to a different page on the same domain. Hence, I made my own solution:
let pathname = location.pathname;
window.addEventListener("click", function() {
if (location.pathname != pathname) {
pathname = location.pathname;
// code
}
});
Edit: You can also check for the popstate event (if a user goes back a page)
window.addEventListener("popstate", function() {
// code
});
Best wishes,
Calculus

If none of the window events are working for you (as they aren't in my case), you can also use a MutationObserver that looks at the root element (non-recursively).
// capture the location at page load
let currentLocation = document.location.href;
const observer = new MutationObserver((mutationList) => {
if (currentLocation !== document.location.href) {
// location changed!
currentLocation = document.location.href;
// (do your event logic here)
}
});
observer.observe(
document.getElementById('root'),
{
childList: true,
// important for performance
subtree: false
});
This may not always be feasible, but typically, if the URL changes, the root element's contents change as well.
I have not profiled, but theoretically this has less overhead than a timer because the Observer pattern is typically implemented so that it just loops through the subscriptions when a change occurs. We only added one subscription here. The timer on the other hand would have to check very frequently in order to ensure that the event was triggered immediately after URL change.
Also, this has a good chance of being more reliable than a timer since it eliminates timing issues.

Although an old question, the Location-bar project is very useful.
var LocationBar = require("location-bar");
var locationBar = new LocationBar();
// listen to all changes to the location bar
locationBar.onChange(function (path) {
console.log("the current url is", path);
});
// listen to a specific change to location bar
// e.g. Backbone builds on top of this method to implement
// it's simple parametrized Backbone.Router
locationBar.route(/some\-regex/, function () {
// only called when the current url matches the regex
});
locationBar.start({
pushState: true
});
// update the address bar and add a new entry in browsers history
locationBar.update("/some/url?param=123");
// update the address bar but don't add the entry in history
locationBar.update("/some/url", {replace: true});
// update the address bar and call the `change` callback
locationBar.update("/some/url", {trigger: true});

To listen to url changes, see below:
window.onpopstate = function(event) {
console.log("location: " + document.location + ", state: " + JSON.stringify(event.state));
};
Use this style if you intend to stop/remove listener after some certain condition.
window.addEventListener('popstate', function(e) {
console.log('url changed')
});

The answer below comes from here(with old javascript syntax(no arrow function, support IE 10+)):
https://stackoverflow.com/a/52809105/9168962
(function() {
if (typeof window.CustomEvent === "function") return false; // If not IE
function CustomEvent(event, params) {
params = params || {bubbles: false, cancelable: false, detail: null};
var evt = document.createEvent("CustomEvent");
evt.initCustomEvent(event, params.bubbles, params.cancelable, params.detail);
return evt;
}
window.CustomEvent = CustomEvent;
})();
(function() {
history.pushState = function (f) {
return function pushState() {
var ret = f.apply(this, arguments);
window.dispatchEvent(new CustomEvent("pushState"));
window.dispatchEvent(new CustomEvent("locationchange"));
return ret;
};
}(history.pushState);
history.replaceState = function (f) {
return function replaceState() {
var ret = f.apply(this, arguments);
window.dispatchEvent(new CustomEvent("replaceState"));
window.dispatchEvent(new CustomEvent("locationchange"));
return ret;
};
}(history.replaceState);
window.addEventListener("popstate", function() {
window.dispatchEvent(new CustomEvent("locationchange"));
});
})();

While doing a little chrome extension, I faced the same problem with an additionnal problem : Sometimes, the page change but not the URL.
For instance, just go to the Facebook Homepage, and click on the 'Home' button. You will reload the page but the URL won't change (one-page app style).
99% of the time, we are developping websites so we can get those events from Frameworks like Angular, React, Vue etc..
BUT, in my case of a Chrome extension (in Vanilla JS), I had to listen to an event that will trigger for each "page change", which can generally be caught by URL changed, but sometimes it doesn't.
My homemade solution was the following :
listen(window.history.length);
var oldLength = -1;
function listen(currentLength) {
if (currentLength != oldLength) {
// Do your stuff here
}
oldLength = window.history.length;
setTimeout(function () {
listen(window.history.length);
}, 1000);
}
So basically the leoneckert solution, applied to window history, which will change when a page changes in a single page app.
Not rocket science, but cleanest solution I found, considering we are only checking an integer equality here, and not bigger objects or the whole DOM.

Found a working answer in a separate thread:
There's no one event that will always work, and monkey patching the pushState event is pretty hit or miss for most major SPAs.
So smart polling is what's worked best for me. You can add as many event types as you like, but these seem to be doing a really good job for me.
Written for TS, but easily modifiable:
const locationChangeEventType = "MY_APP-location-change";
// called on creation and every url change
export function observeUrlChanges(cb: (loc: Location) => any) {
assertLocationChangeObserver();
window.addEventListener(locationChangeEventType, () => cb(window.location));
cb(window.location);
}
function assertLocationChangeObserver() {
const state = window as any as { MY_APP_locationWatchSetup: any };
if (state.MY_APP_locationWatchSetup) { return; }
state.MY_APP_locationWatchSetup = true;
let lastHref = location.href;
["popstate", "click", "keydown", "keyup", "touchstart", "touchend"].forEach((eventType) => {
window.addEventListener(eventType, () => {
requestAnimationFrame(() => {
const currentHref = location.href;
if (currentHref !== lastHref) {
lastHref = currentHref;
window.dispatchEvent(new Event(locationChangeEventType));
}
})
})
});
}
Usage
observeUrlChanges((loc) => {
console.log(loc.href)
})

I created this event that is very similar to the hashchange event
// onurlchange-event.js v1.0.1
(() => {
const hasNativeEvent = Object.keys(window).includes('onurlchange')
if (!hasNativeEvent) {
let oldURL = location.href
setInterval(() => {
const newURL = location.href
if (oldURL === newURL) {
return
}
const urlChangeEvent = new CustomEvent('urlchange', {
detail: {
oldURL,
newURL
}
})
oldURL = newURL
dispatchEvent(urlChangeEvent)
}, 25)
addEventListener('urlchange', event => {
if (typeof(onurlchange) === 'function') {
onurlchange(event)
}
})
}
})()
Example of use:
window.onurlchange = event => {
console.log(event)
console.log(event.detail.oldURL)
console.log(event.detail.newURL)
}
addEventListener('urlchange', event => {
console.log(event)
console.log(event.detail.oldURL)
console.log(event.detail.newURL)
})

for Chrome 102+ (2022-05-24)
navigation.addEventListener("navigate", e => {
console.log(`navigate ->`,e.destination.url)
});
API references WICG/navigation-api

Look at the jQuery unload function. It handles all the things.
https://api.jquery.com/unload/
The unload event is sent to the window element when the user navigates away from the page. This could mean one of many things. The user could have clicked on a link to leave the page, or typed in a new URL in the address bar. The forward and back buttons will trigger the event. Closing the browser window will cause the event to be triggered. Even a page reload will first create an unload event.
$(window).unload(
function(event) {
alert("navigating");
}
);

window.addEventListener("beforeunload", function (e) {
// do something
}, false);

You are starting a new setInterval at each call, without cancelling the previous one - probably you only meant to have a setTimeout

Enjoy!
var previousUrl = '';
var observer = new MutationObserver(function(mutations) {
if (location.href !== previousUrl) {
previousUrl = location.href;
console.log(`URL changed to ${location.href}`);
}
});

Another simple way you can do this is by adding a click event, through a class name to the anchor tags on the page to detect when it has been clicked, then you can now use the window.location.href to get the url data which you can use to run your ajax request to the server. Simple and Easy.