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react history replace disallow back button

I know it's impossible technically to disable user to click the back button of the browser, but it doesn't make sense some time in our app we allow that kind of operation.
For example in my job application app, after you apply you go to next page,
this.props.applyJob({
id: this.state.selectedAd_Id,
applicant_id
}).then(response => {
if(response.value.status === 200){
const { id } = response.value.data.result
this.props.history.replace(`/job/applied/${id}`)
}
})
but user still can go to the previous page which doesn't make sense, how to handle that?

You could try a onunload function of some sort. If the user clicks the button that you want them to click you would have to set a variable so they dont get the warning message.
var showAlert= 1; // this is set to it will show warning when leaving the page
// if they click your next button add this to a function
// showAlert =0;
window.onbeforeunload = function(){
if (showAlert == 1)
return 'Please use the Next and Previous buttons and not the browser back buttons to ensure your date is saved.';
};

Using Confirm() in onbeforeunload() event

I want a confirm box to come up before unloading a page, and if the user clicks ok there a function needs to be called before leaving the page and if he clicks on cancel it should stay on the same page.
window.onbeforeunload = function() {
if (!submitFormOkay) {
if (confirm("Are you sure you want to leave?")) {
leavepage();
} else {
submitfromokay = true;
location.reload();
}
}
}
Is there anyway I can make this work using JS?

No, you can't. The only way to somehow accomplish that goal is by returning a String-value from your onbeforeunload handler. Some browsers (Chrome for instance), will use that String and display it in their default warning message. But other browsers, won't use it and just display a standard message, that gives the user a chance to interrupt the page unload.
// Chrome will use the 'Y U LEAVING' string in its warning message now
window.onbeforeunload = function() {
if(!submitFormOkay) {
return 'Y U LEAVING ?';
}
};

document.getElementById does not return null, but also does not do what I want. No error in javascript console

In this instance, I load a single paypal page, in which I am prompted to login. Once I login, the page changes, through the use of other javascripts on paypal's end. The address does not change on this transition, nor does the source code in any material way. I am trying to find a way to have my script wait long enough after the first click to be able to get the element that loads after. I thought I could do this fairly simple using the following:
document.getElementById("submitLogin").click();
window.onload = function() {
document.getElementById("continue").click();
};
When the script is executed, the first button is clicked, the page transitions, but it won't click the second button that loads. My javascript console does not report any errors, suggesting that it is able to "get" the element. Not sure why it won't click it though.

If nothing else, you could always poll for the existence of the "continue" element at some interval:
function clickContinue() {
var button = document.getElementById("continue");
return button ? button.click() : setTimeout(clickContinue, 100);
}
document.getElementById("submitLogin").click();
clickContinue();
If you go this route, you'll probably want to include a failsafe so it doesn't run too long, in case something unexpected happens. Something like this should work:
clickContinue.interval = 100; // Look for "continue" button every 0.1 second
clickContinue.ttl = 10000; // Approximate time to live: 10 seconds ~ 10,000 ms
clickContinue.tries = clickContinue.ttl / clickContinue.interval | 0;
function clickContinue() {
var button = document.getElementById("continue"),
interval = clickContinue.interval;
return button ? button.click() :
clickContinue.tries-- && setTimeout(clickContinue, interval);
}
// ...
Take a look at PayPal's API docs and see if they provide a way to set up a callback to handle this, though. This polling technique should probably only be used as a last resort.

Prevent a webpage from navigating away using JavaScript

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;

How can I override the OnBeforeUnload dialog and replace it with my own?

I need to warn users about unsaved changes before they leave a page (a pretty common problem).
window.onbeforeunload = handler
This works but it raises a default dialog with an irritating standard message that wraps my own text. I need to either completely replace the standard message, so my text is clear, or (even better) replace the entire dialog with a modal dialog using jQuery.
So far I have failed and I haven't found anyone else who seems to have an answer. Is it even possible?
Javascript in my page:
<script type="text/javascript">
window.onbeforeunload = closeIt;
</script>
The closeIt() function:
function closeIt()
{
if (changes == "true" || files == "true")
{
return "Here you can append a custom message to the default dialog.";
}
}
Using jQuery and jqModal I have tried this kind of thing (using a custom confirm dialog):
$(window).beforeunload(function () {
confirm('new message: ' + this.href + ' !', this.href);
return false;
});
which also doesn't work - I cannot seem to bind to the beforeunload event.

You can't modify the default dialogue for onbeforeunload, so your best bet may be to work with it.
window.onbeforeunload = function() {
return 'You have unsaved changes!';
}
Here's a reference to this from Microsoft:
When a string is assigned to the returnValue property of window.event, a dialog box appears that gives users the option to stay on the current page and retain the string that was assigned to it. The default statement that appears in the dialog box, "Are you sure you want to navigate away from this page? ... Press OK to continue, or Cancel to stay on the current page.", cannot be removed or altered.
The problem seems to be:
When onbeforeunload is called, it will take the return value of the handler as window.event.returnValue.
It will then parse the return value as a string (unless it is null).
Since false is parsed as a string, the dialogue box will fire, which will then pass an appropriate true/false.
The result is, there doesn't seem to be a way of assigning false to onbeforeunload to prevent it from the default dialogue.
Additional notes on jQuery:
Setting the event in jQuery may be problematic, as that allows other onbeforeunload events to occur as well. If you wish only for your unload event to occur I'd stick to plain ol' JavaScript for it.
jQuery doesn't have a shortcut for onbeforeunload so you'd have to use the generic bind syntax.
$(window).bind('beforeunload', function() {} );
Edit 09/04/2018: custom messages in onbeforeunload dialogs are deprecated since chrome-51 (cf: release note)

What worked for me, using jQuery and tested in IE8, Chrome and Firefox, is:
$(window).bind("beforeunload",function(event) {
if(hasChanged) return "You have unsaved changes";
});
It is important not to return anything if no prompt is required as there are differences between IE and other browser behaviours here.

While there isn't anything you can do about the box in some circumstances, you can intercept someone clicking on a link. For me, this was worth the effort for most scenarios and as a fallback, I've left the unload event.
I've used Boxy instead of the standard jQuery Dialog, it is available here: http://onehackoranother.com/projects/jquery/boxy/
$(':input').change(function() {
if(!is_dirty){
// When the user changes a field on this page, set our is_dirty flag.
is_dirty = true;
}
});
$('a').mousedown(function(e) {
if(is_dirty) {
// if the user navigates away from this page via an anchor link,
// popup a new boxy confirmation.
answer = Boxy.confirm("You have made some changes which you might want to save.");
}
});
window.onbeforeunload = function() {
if((is_dirty)&&(!answer)){
// call this if the box wasn't shown.
return 'You have made some changes which you might want to save.';
}
};
You could attach to another event, and filter more on what kind of anchor was clicked, but this works for me and what I want to do and serves as an example for others to use or improve. Thought I would share this for those wanting this solution.
I have cut out code, so this may not work as is.

1) Use onbeforeunload, not onunload.
2) The important thing is to avoid executing a return statement. I don't mean, by this, to avoid returning from your handler. You return all right, but you do it by ensuring that you reach the end of the function and DO NOT execute a return statement. Under these conditions the built-in standard dialog does not occur.
3) You can, if you use onbeforeunload, run an ajax call in your unbeforeunload handler to tidy up on the server, but it must be a synchronous one, and you have to wait for and handle the reply in your onbeforeunload handler (still respecting condition (2) above). I do this and it works fine. If you do a synchronous ajax call, everything is held up until the response comes back. If you do an asynchronous one, thinking that you don't care about the reply from the server, the page unload continues and your ajax call is aborted by this process - including a remote script if it's running.

This can't be done in chrome now to avoid spamming, refer to javascript onbeforeunload not showing custom message for more details.

Angular 9 approach:
constructor() {
window.addEventListener('beforeunload', (event: BeforeUnloadEvent) => {
if (this.generatedBarcodeIndex) {
event.preventDefault(); // for Firefox
event.returnValue = ''; // for Chrome
return '';
}
return false;
});
}
Browsers support and the removal of the custom message:
Chrome removed support for the custom message in ver 51 min
Opera removed support for the custom message in ver 38 min
Firefox removed support for the custom message in ver 44.0 min
Safari removed support for the custom message in ver 9.1 min

Try placing a return; instead of a message.. this is working most browsers for me.
(This only really prevents dialog's presents)
window.onbeforeunload = function(evt) {
//Your Extra Code
return;
}

You can detect which button (ok or cancel) pressed by user, because the onunload function called only when the user choise leaveing the page. Althoug in this funcion the possibilities is limited, because the DOM is being collapsed. You can run javascript, but the ajax POST doesn't do anything therefore you can't use this methode for automatic logout. But there is a solution for that. The window.open('logout.php') executed in the onunload funcion, so the user will logged out with a new window opening.
function onunload = (){
window.open('logout.php');
}
This code called when user leave the page or close the active window and user logged out by 'logout.php'.
The new window close immediately when logout php consist of code:
window.close();

I faced the same problem, I was ok to get its own dialog box with my message, but the problem I faced was :
1) It was giving message on all navigations I want it only for close click.
2) with my own confirmation message if user selects cancel it still shows the browser's default dialog box.
Following is the solutions code I found, which I wrote on my Master page.
function closeMe(evt) {
if (typeof evt == 'undefined') {
evt = window.event; }
if (evt && evt.clientX >= (window.event.screenX - 150) &&
evt.clientY >= -150 && evt.clientY <= 0) {
return "Do you want to log out of your current session?";
}
}
window.onbeforeunload = closeMe;

<script type="text/javascript">
window.onbeforeunload = function(evt) {
var message = 'Are you sure you want to leave?';
if (typeof evt == 'undefined') {
evt = window.event;
}
if (evt) {
evt.returnValue = message;
}
return message;
}
</script>
refer from http://www.codeprojectdownload.com

What about to use the specialized version of the "bind" command "one". Once the event handler executes the first time, it’s automatically removed as an event handler.
$(window).one("beforeunload", BeforeUnload);

Try this
$(window).bind('beforeunload', function (event) {
setTimeout(function () {
var retVal = confirm("Do you want to continue ?");
if (retVal == true) {
alert("User wants to continue!");
return true;
}
else {
window.stop();
return false;
}
});
return;
});