I want using JavaScript to see if there is history or not, I mean if the back button is available on the browser or not.
Short answer: You can't.
Technically there is an accurate way, which would be checking the property:
history.previous
However, it won't work. The problem with this is that in most browsers this is considered a security violation and usually just returns undefined.
history.length
Is a property that others have suggested...
However, the length doesn't work completely because it doesn't indicate where in the history you are. Additionally, it doesn't always start at the same number. A browser not set to have a landing page, for example, starts at 0 while another browser that uses a landing page will start at 1.
Most of the time a link is added that calls:
history.back();
or
history.go(-1);
and it's just expected that if you can't go back then clicking the link does nothing.
There is another way to check - check the referrer. The first page usually will have an empty referrer...
if (document.referrer == "") {
window.close()
} else {
history.back()
}
My code let the browser go back one page, and if that fails it loads a fallback url. It also detect hashtags changes.
When the back button wasn't available, the fallback url will be loaded after 500 ms, so the browser has time enough to load the previous page. Loading the fallback url right after window.history.go(-1); would cause the browser to use the fallback url, because the js script didn't stop yet.
function historyBackWFallback(fallbackUrl) {
fallbackUrl = fallbackUrl || '/';
var prevPage = window.location.href;
window.history.go(-1);
setTimeout(function(){
if (window.location.href == prevPage) {
window.location.href = fallbackUrl;
}
}, 500);
}
Here is how i did it.
I used the 'beforeunload' event to set a boolean. Then I set a timeout to watch if the 'beforeunload' fired.
var $window = $(window),
$trigger = $('.select_your_link'),
fallback = 'your_fallback_url';
hasHistory = false;
$window.on('beforeunload', function(){
hasHistory = true;
});
$trigger.on('click', function(){
window.history.go(-1);
setTimeout(function(){
if (!hasHistory){
window.location.href = fallback;
}
}, 200);
return false;
});
Seems to work in major browsers (tested FF, Chrome, IE11 so far).
There is a snippet I use in my projects:
function back(url) {
if (history.length > 2) {
// if history is not empty, go back:
window.History.back();
} else if (url) {
// go to specified fallback url:
window.History.replaceState(null, null, url);
} else {
// go home:
window.History.replaceState(null, null, '/');
}
}
FYI: I use History.js to manage browser history.
Why to compare history.length to number 2?
Because Chrome's startpage is counted as first item in the browser's history.
There are few possibilities of history.length and user's behaviour:
User opens new empty tab in the browser and then runs a page. history.length = 2 and we want to disable back() in this case, because user will go to empty tab.
User opens the page in new tab by clicking a link somewhere before. history.length = 1 and again we want to disable back() method.
And finally, user lands at current page after reloading few pages. history.length > 2 and now back() can be enabled.
Note: I omit case when user lands at current page after clicking link from external website without target="_blank".
Note 2: document.referrer is empty when you open website by typing its address and also when website uses ajax to load subpages, so I discontinued checking this value in the first case.
this seems to do the trick:
function goBackOrClose() {
window.history.back();
window.close();
//or if you are not interested in closing the window, do something else here
//e.g.
theBrowserCantGoBack();
}
Call history.back() and then window.close(). If the browser is able to go back in history it won't be able to get to the next statement. If it's not able to go back, it'll close the window.
However, please note that if the page has been reached by typing a url, then firefox wont allow the script to close the window.
Be careful with window.history.length because it also includes entries for window.history.forward()
So you may have maybe window.history.length with more than 1 entries, but no history back entries.
This means that nothing happens if you fire window.history.back()
You can't directly check whether the back button is usable. You can look at history.length>0, but that will hold true if there are pages ahead of the current page as well. You can only be sure that the back button is unusable when history.length===0.
If that's not good enough, about all you can do is call history.back() and, if your page is still loaded afterwards, the back button is unavailable! Of course that means if the back button is available, you've just navigated away from the page. You aren't allowed to cancel the navigation in onunload, so about all you can do to stop the back actually happening is to return something from onbeforeunload, which will result in a big annoying prompt appearing. It's not worth it.
In fact it's normally a Really Bad Idea to be doing anything with the history. History navigation is for browser chrome, not web pages. Adding “go back” links typically causes more user confusion than it's worth.
history.length is useless as it does not show if user can go back in history.
Also different browsers uses initial values 0 or 1 - it depends on browser.
The working solution is to use $(window).on('beforeunload' event, but I'm not sure that it will work if page is loaded via ajax and uses pushState to change window history.
So I've used next solution:
var currentUrl = window.location.href;
window.history.back();
setTimeout(function(){
// if location was not changed in 100 ms, then there is no history back
if(currentUrl === window.location.href){
// redirect to site root
window.location.href = '/';
}
}, 100);
Building on the answer here and here. I think, the more conclusive answer is just to check if this is a new page in a new tab.
If the history of the page is more than one, then we can go back to the page previous to the current page. If not, the tab is a newly opened tab and we need to create a new tab.
Differently, to the answers linked, we are not checking for a referrer as a new tab will still have a referrer.
if(1 < history.length) {
history.back();
}
else {
window.close();
}
This work for me using react but can work in another case; when history is in the first page (you cannot go back) window.history.state will be null, so if you want to know if you can navigate back you only need:
if (window.history.state == null) {
//you cannot go back
}
Documentation:
The History.state property returns a value representing the state at
the top of the history stack. This is a way to look at the state
without having to wait for a popstate event.
I was trying to find a solution and this is the best i could get (but works great and it's the easiest solution i've found even here).
In my case, i wanted to go back on history with an back button, but if the first page the user opened was an subpage of my app, it would go back to the main page.
The solution was, as soon the app is loaded, i just did an replace on the history state:
history.replaceState( {root: true}, '', window.location.pathname + window.location.hash)
This way, i just need to check history.state.root before go back. If true, i make an history replace instead:
if(history.state && history.state.root)
history.replaceState( {root: true}, '', '/')
else
history.back()
I came up with the following approach. It utilizes the onbeforeunload event to detect whether the browser starts leaving the page or not. If it does not in a certain timespan it'll just redirect to the fallback.
var goBack = function goBack(fallback){
var useFallback = true;
window.addEventListener("beforeunload", function(){
useFallback = false;
});
window.history.back();
setTimeout(function(){
if (useFallback){ window.location.href = fallback; }
}, 100);
}
You can call this function using goBack("fallback.example.org").
There is another near perfect solution, taken from another SO answer:
if( (1 < history.length) && document.referrer ) {
history.back();
}
else {
// If you can't go back in history, you could perhaps close the window ?
window.close();
}
Someone reported that it does not work when using target="_blank" but it seems to work for me on Chrome.
the browser has back and forward button. I come up a solution on this question. but It will affect browser forward action and cause bug with some browsers.
It works like that: If the browser open a new url, that has never opened, the history.length will be grow.
so you can change hash like
location.href = '#__transfer__' + new Date().getTime()
to get a never shown url, then history.length will get the true length.
var realHistoryLength = history.length - 1
but, It not always work well, and I don't known why ,especially the when url auto jump quickly.
I am using window.history in Angular for the FAQ on my site.
Whenever the user wants to exit the FAQ they can click the exit button (next to the back button)
My logic for this "exit" strategy is based on the entry ID and then just go back the number of states till that state.
So on enter:
enterState: { navigationId:number } = {navigationId: 1}
constructor() {
this.enterState = window.history.state
}
pretent the user navigates through the faq
And then, when the user clicks the exit button, read the current state and calculate your delta:
exitFaq() {
// when user started in faq, go back to first state, replace it with home and navigate
if (this.enterState.navigationId === 1) {
window.history.go((window.history.state.navigationId - 1) * -1)
this.router.navigateByUrl('/')
// non-angular
// const obj = {Title: 'Home', Url: '/'}
// window.history.replaceState(obj, obj.Title, obj.Url)
} else {
window.history.go(this.enterState.navigationId - window.history.state.navigationId - 1)
}
}
As you can see, I also use a fallback for when the user started in the faq, in that case the state.navigationId is 1 and we want to route back, replace the first state and show the homepage (For this I'm using the Angular router, but you can use history.replaceState as well when you handle your own routes)
For reference:
history.go
history.state
history.replaceState
Angular.router.navigateByUrl
This might help:
const prev = window.location.pathname;
window.history.back();
setTimeout(() => {
if (prev === window.location.pathname) {
// Do something else ...
}
}, 1000);
I'm using Angular, I need to check if there is history, trigger location.back(), else redirect to parent route.
Solution from https://stackoverflow.com/a/69572533/18856708 works well.
constructor(
private activatedRoute: ActivatedRoute,
private router: Router,
private location: Location,
}
...
back(): void {
if (window.history.state === null) {
this.router.navigate(['../'], { relativeTo: this.activatedRoute });
return;
}
this.location.back();
}
This is my solution:
function historyBack() {
console.log('back');
window.history.back() || window.history.go(-1);
if (!window.history.length) window.close();
var currentUrl = window.location.href;
setTimeout(function(){
// if location was not changed in 100 ms, then there is no history back
if(current === window.location.href){
console.log('History back is empty!');
}
}, 100);
}
function historyForward() {
console.log('forward');
window.history.forward() || window.history.go(+1);
var current = window.location.href;
setTimeout(function(){
// if location was not changed in 100 ms, then there is no history forward
if(current === window.location.href){
console.log('History forward is empty!');
}
}, 100);
}
The following solution will navigate back AND will tell if the navigation occurred or not:
async function goBack() {
return new Promise((resolve, reject) => {
const timer = setTimeout(() => reject('nowhere to go'), 100);
window.history.back();
const onBack = () => {
window.removeEventListener('beforeunload', onBack);
window.removeEventListener('popstate', onBack);
clearTimeout(timer);
resolve(true);
};
window.addEventListener('beforeunload', onBack);
window.addEventListener('popstate', onBack);
});
}
// usage
await goBack().catch(err => console.log('failed'));
How it works:
Try to navigate back
Add event listeners that will trigger on navigation to another website or to another page on the same site (SPA website, etc.)
If above events didn't occur in 100ms, deduce that there's nowhere to go back to
Notice that goBack() is an async function.
var fallbackUrl = "home.php";
if(history.back() === undefined)
window.location.href = fallbackUrl;
I am using a bit of PHP to achieve the result. It's a bit rusty though. But it should work.
<?php
function pref(){
return (isset($_SERVER['HTTP_REFERER'])) ? true : '';
}
?>
<html>
<body>
<input type="hidden" id="_pref" value="<?=pref()?>">
<button type="button" id="myButton">GoBack</button>
<!-- Include jquery library -->
<script>
if (!$('#_pref').val()) {
$('#myButton').hide() // or $('#myButton').remove()
}
</script>
</body>
</html>
var func = function(){ console.log("do something"); };
if(document.referrer.includes(window.location.hostname) && history.length-1 <= 1){
func();
}
else{
const currentUrl = window.location.href;
history.back();
setTimeout(function(){
currentUrl === window.location.href && func();
}, 100);
}
I found a JQuery solution that actually works
window.history.length == 1
This works on Chrome, Firefox, and Edge.
You can use the following piece of JQuery code that worked for me on the latest versions of all of the above 3 browsers if you want to hide or remove a back button on your developed web page when there is no window history.
$(window).load(function() {
if (window.history.length == 1) {
$("#back-button").remove();
}
})
Solution
'use strict';
function previousPage() {
if (window.location.pathname.split('/').filter(({ length }) => length > 0).length > 0) {
window.history.back();
}
}
Explaination
window.location.pathname will give you the current URI. For instance https://domain/question/1234/i-have-a-problem will give /question/1234/i-have-a-problem. See the documentation about window.location for more informations.
Next, the call to split() will give us all fragments of that URI. so if we take our previous URI, we will have something like ["", "question", "1234", "i-have-a-problem"]. See the documentation about String.prototype.split() for more informations.
The call to filter() is here to filter out the empty string generated by the backward slash. It will basically return only the fragment URI that have a length greater than 1 (non-empty string). So we would have something like ["question", "1234", "i-have-a-question"]. This could have been writen like so:
'use strict';
window.location.pathname.split('/').filter(function(fragment) {
return fragment.length > 0;
});
See the documentation about Array.prototype.filter() and the Destructuring assignment for more informations.
Now, if the user tries to go back while being on https://domain/, we wont trigger the if-statement, and so wont trigger the window.history.back() method so the user will stay in our website. This URL will be equivalent to [] which has a length of 0, and 0 > 0 is false. Hence, silently failing. Of course, you can log something or have another action if you want.
'use strict';
function previousPage() {
if (window.location.pathname.split('/').filter(({ length }) => length > 0).length > 0) {
window.history.back();
} else {
alert('You cannot go back any further...');
}
}
Limitations
Of course, this solution wont work if the browser do not support the History API. Check the documentation to know more about it before using this solution.
I'm not sure if this works and it is completely untested, but try this:
<script type="text/javascript">
function goBack() {
history.back();
}
if (history.length > 0) { //if there is a history...
document.getElementsByTagName('button')[].onclick="goBack()"; //assign function "goBack()" to all buttons onClick
} else {
die();
}
</script>
And somewhere in HTML:
<button value="Button1"> //These buttons have no action
<button value="Button2">
EDIT:
What you can also do is to research what browsers support the back function (I think they all do) and use the standard JavaScript browser detection object found, and described thoroughly, on this page. Then you can have 2 different pages: one for the "good browsers" compatible with the back button and one for the "bad browsers" telling them to go update their browser
Check if window.history.length is equal to 0.
Related
I have a function named back() which will be used for ajax calls. Actually I have an array stack contains last 5 search results and that back function will switch to the previous result set (according to that array stack) and it even changes the URL using window.history.pushState() when you click on the back button.
That back button I was talking about, is an element inside the browser which revokes back() function. Now I want to revoke back() function also when user click on the back button of the browser. Something like this:
window.onhashchange = function() {
back(); // this function also changes the url
}
But sadly window.onhashchange will be revokes twice when I click on the back of the browser. Because window.onhashchange will be revoked when you change the URL using window.history.pushState().
Anyway, how can I detect what things changes the URL? Either my JS code or the back button of the browser?
You can use performance.navigation.type
At any given point, for example on document.onload, you can read the value of type and, if it's:
0 The page was accessed by following a link, a bookmark, a form submission, a script, or typing the URL in the address bar.
1 The page was accessed by clicking the Reload button or via the Location.reload() method.
2 The page was accessed by navigating into the history.
255 any other way.
Just beware that support is limited according to the compatibilty table.
However, from the looks of it, it seems the table is outdated. It says it is not supported on chrome and I just tested it and works as expected on my chrome version (67.0)
One of solution is to implement onunload event with localstorage option.
This is from my head maybe you will need correction but this is base !
var history = [];
window.onload = function(){
var handler;
if ( localStorage.getItem('history') == null ) {
// FIRST TIME
history[0] = window.location.href;
localStorage.setItem("history", JSON.stringify(history));
}
else {
handler = localStorage.getItem('history');
handler = JSON.parse(handler);
history = handler;
// Just compare now
if (history[history.length-1] == window.location.href) {
// no change
} else {
history.push(window.location.href);
}
}
}
window.onunload = function(){
localStorage.setItem('history', JSON.stringify(history));
}
Note :
Since 25 May 2011, the HTML5 specification states that calls to
window.alert(), window.confirm(), and window.prompt() methods may be
ignored during this event. See the HTML5 specification for more
details.
Using the HTML5 window.history API, I can control the navigation pretty well on my web app.
The app currently has two states: selectDate (1) and enterDetails (2).
When the app loads, I replaceState and set a popState listener:
history.replaceState({stage:"selectDate",...},...);
window.onpopstate = function(event) {
that.toStage(event.state.stage);
};
When a date is selected and the app moves to stage 2 I push state 2 onto the stack:
history.pushState({stage:"enterDetails",...},...);
This state is replaced anytime details change so they are saved in the history.
There are three ways to leave stage 2:
save (AJAX submit)
cancel
back button
The back button is handled by the popstate listener. The cancel button pushes stage 1 so that the user can go back to the details they were entering the back button. These both work well.
The save button should revert back to stage 1 and not allow the user to navigate back to the details page (since they already submitted). Basical, y it should make the history stack be length = 1.
But there doesn't seem to be a history.delete(), or history.merge(). The best I can do is a history.replaceState(stage1) which leaves the history stack as: ["selectDate","selectDate"].
How do I get rid of one layer?
Edit:
Thought of something else, but it doesn't work either.
history.back(); //moves history to the correct position
location.href = "#foo"; // successfully removes ability to go 'forward',
// but also adds another layer to the history stack
This leaves the history stack as ["selectDate","selectDate#foo"].
So, as an alternative, is there a way to remove the 'forward' history without pushing a new state?
You may have moved on by now, but... as far as I know there's no way to delete a history entry (or state).
One option I've been looking into is to handle the history yourself in JavaScript and use the window.history object as a carrier of sorts.
Basically, when the page first loads you create your custom history object (we'll go with an array here, but use whatever makes sense for your situation), then do your initial pushState. I would pass your custom history object as the state object, as it may come in handy if you also need to handle users navigating away from your app and coming back later.
var myHistory = [];
function pageLoad() {
window.history.pushState(myHistory, "<name>", "<url>");
//Load page data.
}
Now when you navigate, you add to your own history object (or don't - the history is now in your hands!) and use replaceState to keep the browser out of the loop.
function nav_to_details() {
myHistory.push("page_im_on_now");
window.history.replaceState(myHistory, "<name>", "<url>");
//Load page data.
}
When the user navigates backwards, they'll be hitting your "base" state (your state object will be null) and you can handle the navigation according to your custom history object. Afterward, you do another pushState.
function on_popState() {
// Note that some browsers fire popState on initial load,
// so you should check your state object and handle things accordingly.
// (I did not do that in these examples!)
if (myHistory.length > 0) {
var pg = myHistory.pop();
window.history.pushState(myHistory, "<name>", "<url>");
//Load page data for "pg".
} else {
//No "history" - let them exit or keep them in the app.
}
}
The user will never be able to navigate forward using their browser buttons because they are always on the newest page.
From the browser's perspective, every time they go "back", they've immediately pushed forward again.
From the user's perspective, they're able to navigate backwards through the pages but not forward (basically simulating the smartphone "page stack" model).
From the developer's perspective, you now have a high level of control over how the user navigates through your application, while still allowing them to use the familiar navigation buttons on their browser. You can add/remove items from anywhere in the history chain as you please. If you use objects in your history array, you can track extra information about the pages as well (like field contents and whatnot).
If you need to handle user-initiated navigation (like the user changing the URL in a hash-based navigation scheme), then you might use a slightly different approach like...
var myHistory = [];
function pageLoad() {
// When the user first hits your page...
// Check the state to see what's going on.
if (window.history.state === null) {
// If the state is null, this is a NEW navigation,
// the user has navigated to your page directly (not using back/forward).
// First we establish a "back" page to catch backward navigation.
window.history.replaceState(
{ isBackPage: true },
"<back>",
"<back>"
);
// Then push an "app" page on top of that - this is where the user will sit.
// (As browsers vary, it might be safer to put this in a short setTimeout).
window.history.pushState(
{ isBackPage: false },
"<name>",
"<url>"
);
// We also need to start our history tracking.
myHistory.push("<whatever>");
return;
}
// If the state is NOT null, then the user is returning to our app via history navigation.
// (Load up the page based on the last entry of myHistory here)
if (window.history.state.isBackPage) {
// If the user came into our app via the back page,
// you can either push them forward one more step or just use pushState as above.
window.history.go(1);
// or window.history.pushState({ isBackPage: false }, "<name>", "<url>");
}
setTimeout(function() {
// Add our popstate event listener - doing it here should remove
// the issue of dealing with the browser firing it on initial page load.
window.addEventListener("popstate", on_popstate);
}, 100);
}
function on_popstate(e) {
if (e.state === null) {
// If there's no state at all, then the user must have navigated to a new hash.
// <Look at what they've done, maybe by reading the hash from the URL>
// <Change/load the new page and push it onto the myHistory stack>
// <Alternatively, ignore their navigation attempt by NOT loading anything new or adding to myHistory>
// Undo what they've done (as far as navigation) by kicking them backwards to the "app" page
window.history.go(-1);
// Optionally, you can throw another replaceState in here, e.g. if you want to change the visible URL.
// This would also prevent them from using the "forward" button to return to the new hash.
window.history.replaceState(
{ isBackPage: false },
"<new name>",
"<new url>"
);
} else {
if (e.state.isBackPage) {
// If there is state and it's the 'back' page...
if (myHistory.length > 0) {
// Pull/load the page from our custom history...
var pg = myHistory.pop();
// <load/render/whatever>
// And push them to our "app" page again
window.history.pushState(
{ isBackPage: false },
"<name>",
"<url>"
);
} else {
// No more history - let them exit or keep them in the app.
}
}
// Implied 'else' here - if there is state and it's NOT the 'back' page
// then we can ignore it since we're already on the page we want.
// (This is the case when we push the user back with window.history.go(-1) above)
}
}
There is no way to delete or read the past history.
You could try going around it by emulating history in your own memory and calling history.pushState everytime window popstate event is emitted (which is proposed by the currently accepted Mike's answer), but it has a lot of disadvantages that will result in even worse UX than not supporting the browser history at all in your dynamic web app, because:
popstate event can happen when user goes back ~2-3 states to the past
popstate event can happen when user goes forward
So even if you try going around it by building virtual history, it's very likely that it can also lead into a situation where you have blank history states (to which going back/forward does nothing), or where that going back/forward skips some of your history states totally.
A simple solution:
var ismobilescreen = $(window).width() < 480;
var backhistory_pushed = false;
$('.editbtn').click( function()
{
// push to browser history, so back button will close the editor
// and not navigate away from site
if (ismobilescreen && !backhistory_pushed)
{
window.history.pushState('forward', null, window.location);
backhistory_pushed = true;
}
}
Then:
if (window.history && window.history.pushState)
{
$(window).on('popstate', function()
{
if (ismobilescreen && backhistory_pushed && $('.editor').is(':visible'))
{
// hide editor window (we initiate a click on the cancel button)
$('.editor:visible .cancelbtn').click();
backhistory_pushed = false;
}
});
}
Results in:
User opens editor DIV, the history state is saved.
User hits back button, history state is taken into account.
Users stays on page!
Instead of navigating back, the editor DIV is closed.
One issue: If you use a "Cancel" button on your DIV and this hides the editor, then the user has to click the mobile's back button two times to go back to the previous URL.
To solve this problem you can call window.history.back(); to remove the history entry by yourself which actually deletes the state as requested.
For example:
$('.btn-cancel').click( function()
{
if (ismobilescreen && backhistory_pushed)
{
window.history.back();
}
}
Alternatively you could push a URL into the history that holds an anchor, e.g. #editor and then push to history or not if the anchor exists in the recent URL or not.
I’ve made a one page site. When user clicks on the menu buttons, content is loaded with ajax.
It works fine.
In order to improve SEO and to allow user to copy / past URL of different content, i use
function show_content() {
// change URL in browser bar)
window.history.pushState("", "Content", "/content.php");
// ajax
$content.load("ajax/content.php?id="+id);
}
It works fine. URL changes and the browser doesn’t reload the page
However, when user clicks on back button in browser, the url changes and the content have to be loaded.
I've done this and it works :
window.onpopstate = function(event) {
if (document.location.pathname == '/4-content.php') {
show_content_1();
}
else if (document.location.pathname == '/1-content.php') {
show_content_2();
}
else if (document.location.pathname == '/6-content.php') {
show_content_();
}
};
Do you know if there is a way to improve this code ?
What I did was passing an object literal to pushState() on page load. This way you can always go back to your first created pushState. In my case I had to push twice before I could go back. Pushing a state on page load helped me out.
HTML5 allows you to use data-attributes so for your triggers you can use those to bind HTML data.
I use a try catch because I didn't had time to find a polyfill for older browsers. You might want to check Modernizr if this is needed in your case.
PAGELOAD
try {
window.history.pushState({
url: '',
id: this.content.data("id"), // html data-id
label: this.content.data("label") // html data-label
}, "just content or your label variable", window.location.href);
} catch (e) {
console.log(e);
}
EVENT HANDLERS
An object filled with default information
var obj = {
url: settings.assetsPath, // this came from php
lang: settings.language, // this came from php
historyData: {}
};
Bind the history.pushState() trigger. In my case a delegate since I have dynamic elements on the page.
// click a trigger -> push state
this.root.on("click", ".cssSelector", function (ev) {
var path = [],
urlChunk = document.location.pathname; // to follow your example
// some data-attributes you need? like id or label
// override obj.historyData
obj.historyData.id = $(ev.currentTarget).data("id");
// create a relative path for security reasons
path.push("..", obj.lang, label, urlChunk);
path = path.join("/");
// attempt to push a state
try {
window.history.pushState(obj.historyData, label, path);
this.back.fadeIn();
this.showContent(obj.historyData.id);
} catch (e) {
console.log(e);
}
});
Bind the history.back() event to a custom button, link or something.
I used .preventDefault() since my button is a link.
// click back arrow -> history
this.back.on("click", function (ev) {
ev.preventDefault();
window.history.back();
});
When history pops back -> check for a pushed state unless it was the first attempt
$(window).on("popstate", function (ev) {
var originalState = ev.originalEvent.state || obj.historyData;
if (!originalState) {
// no history, hide the back button or something
this.back.fadeOut();
return;
} else {
// do something
this.showContent(obj.historyData.id);
}
});
Using object literals as a parameter is handy to pass your id's. Then you can use one function showContent(id).
Wherever I've used this it's nothing more than a jQuery object/function, stored inside an IIFE.
Please note I put these scripts together from my implementation combined with some ideas from your initial request. So hopefully this gives you some new ideas ;)
I tried to build a JS script that would change the location of the page, to go back until a specific hash location is found:
var StopAtThisHash ='#';
var CurrentHash = window.location.hash;
var continueLoop = true;
while ((window.history.length>0) && (continueLoop))
{
window.history.back();
var NowWeAreAtHash = window.location.hash; //this never changes in Chrome
//actually, always seems to: CurrentHash == NowWeAreAtHash;
if(NowWeAreAtHash == StopAtThisHash)
continueLoop= false;
}
Weird enough, in Chrome and FF, the window.location.hash is not changed after back().. neither is the length of history decreased by 1 as I expected. The loop runs indefinitely, and the browser hangs up.
In IE 9 this seems to run as intended.
Any workarounds around this?
function goBackHome () {
goBackToHash(''); // Assume the home is without hash. You can use '#'.
}
function goBackToHash(hash) {
setTimeout(function () {
if (window.location.hash == hash) return;
history.back();
goBackToHash(hash);
}, 0);
}
To overcome the problem of while loop, I tried use setTimeout, but this is usually goes further than expected... Waiting for a perfect solution.
I think there is a delay between history.back() and when window.location.hash is changed.
Another workaround is to keep the hashes in JS so that you can figure out how many steps is needed in history.go(N).
Seems that window.history.back(), window.history.forward() and window.history.go() does not changes history, just navigates back and forth. If back() would change length of history then you would not be able to forward().
As workaround I would suggest to loop over window.history with for from last to first instead of while.
How to prevent a webpage from navigating away using JavaScript?
Using onunload allows you to display messages, but will not interrupt the navigation (because it is too late). However, using onbeforeunload will interrupt navigation:
window.onbeforeunload = function() {
return "";
}
Note: An empty string is returned because newer browsers provide a message such as "Any unsaved changes will be lost" that cannot be overridden.
In older browsers you could specify the message to display in the prompt:
window.onbeforeunload = function() {
return "Are you sure you want to navigate away?";
}
Unlike other methods presented here, this bit of code will not cause the browser to display a warning asking the user if he wants to leave; instead, it exploits the evented nature of the DOM to redirect back to the current page (and thus cancel navigation) before the browser has a chance to unload it from memory.
Since it works by short-circuiting navigation directly, it cannot be used to prevent the page from being closed; however, it can be used to disable frame-busting.
(function () {
var location = window.document.location;
var preventNavigation = function () {
var originalHashValue = location.hash;
window.setTimeout(function () {
location.hash = 'preventNavigation' + ~~ (9999 * Math.random());
location.hash = originalHashValue;
}, 0);
};
window.addEventListener('beforeunload', preventNavigation, false);
window.addEventListener('unload', preventNavigation, false);
})();
Disclaimer: You should never do this. If a page has frame-busting code on it, please respect the wishes of the author.
The equivalent in a more modern and browser compatible way, using modern addEventListener APIs.
window.addEventListener('beforeunload', (event) => {
// Cancel the event as stated by the standard.
event.preventDefault();
// Chrome requires returnValue to be set.
event.returnValue = '';
});
Source: https://developer.mozilla.org/en-US/docs/Web/Events/beforeunload
I ended up with this slightly different version:
var dirty = false;
window.onbeforeunload = function() {
return dirty ? "If you leave this page you will lose your unsaved changes." : null;
}
Elsewhere I set the dirty flag to true when the form gets dirtied (or I otherwise want to prevent navigating away). This allows me to easily control whether or not the user gets the Confirm Navigation prompt.
With the text in the selected answer you see redundant prompts:
In Ayman's example by returning false you prevent the browser window/tab from closing.
window.onunload = function () {
alert('You are trying to leave.');
return false;
}
The equivalent to the accepted answer in jQuery 1.11:
$(window).on("beforeunload", function () {
return "Please don't leave me!";
});
JSFiddle example
altCognito's answer used the unload event, which happens too late for JavaScript to abort the navigation.
That suggested error message may duplicate the error message the browser already displays. In chrome, the 2 similar error messages are displayed one after another in the same window.
In chrome, the text displayed after the custom message is: "Are you sure you want to leave this page?". In firefox, it does not display our custom error message at all (but still displays the dialog).
A more appropriate error message might be:
window.onbeforeunload = function() {
return "If you leave this page, you will lose any unsaved changes.";
}
Or stackoverflow style: "You have started writing or editing a post."
If you are catching a browser back/forward button and don't want to navigate away, you can use:
window.addEventListener('popstate', function() {
if (window.location.origin !== 'http://example.com') {
// Do something if not your domain
} else if (window.location.href === 'http://example.com/sign-in/step-1') {
window.history.go(2); // Skip the already-signed-in pages if the forward button was clicked
} else if (window.location.href === 'http://example.com/sign-in/step-2') {
window.history.go(-2); // Skip the already-signed-in pages if the back button was clicked
} else {
// Let it do its thing
}
});
Otherwise, you can use the beforeunload event, but the message may or may not work cross-browser, and requires returning something that forces a built-in prompt.
Use onunload.
For jQuery, I think this works like so:
$(window).unload(function() {
alert("Unloading");
return falseIfYouWantToButBeCareful();
});
If you need to toggle the state back to no notification on exit, use the following line:
window.onbeforeunload = null;