Once the user is on my page, I do not want him to refresh the page.
Anytime, the user hits F5 or refresh button on top. He should get an alert saying
You cannot refresh the page.
Also if the user opens a new tab and tries to access the same url in prev tab he should get an alert
You cannot open same page in 2 tabs
Anyway I can do this using JavaScript or jQuery? Point one is really important.
#1 can be implemented via window.onbeforeunload.
For example:
<script type="text/javascript">
window.onbeforeunload = function() {
return "Dude, are you sure you want to leave? Think of the kittens!";
}
</script>
The user will be prompted with the message, and given an option to stay on the page or continue on their way. This is becoming more common. Stack Overflow does this if you try to navigate away from a page while you are typing a post. You can't completely stop the user from reloading, but you can make it sound real scary if they do.
#2 is more or less impossible. Even if you tracked sessions and user logins, you still wouldn't be able to guarantee that you were detecting a second tab correctly. For example, maybe I have one window open, then close it. Now I open a new window. You would likely detect that as a second tab, even though I already closed the first one. Now your user can't access the first window because they closed it, and they can't access the second window because you're denying them.
In fact, my bank's online system tries real hard to do #2, and the situation described above happens all the time. I usually have to wait until the server-side session expires before I can use the banking system again.
You can't prevent the user from refreshing, nor should you really be trying. You should go back to why you need this solution, what's the root problem here?. Start there and find a different way to go about solving the problem. Perhaps is you elaborated on why you think you need to do this it would help in finding such a solution.
Breaking fundamental browser features is never a good idea, over 99.999999999% of the internet works and refreshes with F5, this is an expectation of the user, one you shouldn't break.
Although its not a good idea to disable F5 key you can do it in JQuery as below.
<script type="text/javascript">
function disableF5(e) { if ((e.which || e.keyCode) == 116 || (e.which || e.keyCode) == 82) e.preventDefault(); };
$(document).ready(function(){
$(document).on("keydown", disableF5);
});
</script>
Hope this will help!
Back in the ole days of CGI we had many forms that would trigger various backend actions. Such as text notifications to groups, print jobs, farming of data, etc.
If the user was on a page that was saying "Please wait... Performing some HUGE job that could take some time.". They were more likely to hit REFRESH and this would be BAD!
WHY? Because it would trigger more slow jobs and eventually bog down the whole thing.
The solution?
Allow them to do their form.
When they submit their form... Start your job and then direct them to another page that tells them to wait.
Where the page in the middle actually held the form data that was needed to start the job.
The WAIT page however contains a javascript history destroy. So they can RELOAD that wait page all they want and it will never trigger the original job to start in the background as that WAIT page only contains the form data needed for the WAIT itself.
Hope that makes sense.
The history destroy function also prevented them from clicking BACK and then refreshing as well.
It was very seamless and worked great for MANY MANY years until the non-profit was wound down.
Example:
FORM ENTRY - Collect all their info and when submitted, this triggers your backend job.
RESPONSE from form entry - Returns HTML that performs a redirect to your static wait page and/or POST/GET to another form (the WAIT page).
WAIT PAGE - Only contains FORM data related to wait page as well as javascript to destroy the most recent history. Like (-1 OR -2) to only destroy the most recent pages, but still allows them to go back to their original FORM entry page.
Once they are at your WAIT page, they can click REFRESH as much as they want and it will never spawn the original FORM job on the backend. Instead, your WAIT page should embrace a META timed refresh itself so it can always check on the status of their job. When their job is completed, they are redirected away from the wait page to whereever you wish.
If they do manually REFRESH... They are simply adding one more check of their job status in there.
Hope that helps. Good luck.
No, there isn't.
I'm pretty sure there is no way to intercept a click on the refresh button from JS, and even if there was, JS can be turned off.
You should probably step back from your X (preventing refreshing) and find a different solution to Y (whatever that might be).
Issue #2 now can be solved using BroadcastAPI.
At the moment it's only available in Chrome, Firefox, and Opera.
var bc = new BroadcastChannel('test_channel');
bc.onmessage = function (ev) {
if(ev.data && ev.data.url===window.location.href){
alert('You cannot open the same page in 2 tabs');
}
}
bc.postMessage(window.location.href);
Number (2) is possible by using a socket implementation (like websocket, socket.io, etc.) with a custom heartbeat for each session the user is engaged in. If a user attempts to open another window, you have a javascript handler check with the server if it's ok, and then respond with an error messages.
However, a better solution is to synchronize the two sessions if possible like in google docs.
Related
I am creating a web app using web socket, which on user closes the tab I will make an API call to the server to clean the user related info in the server, I used onBeforeUnload listener in javascript, but this method also gets triggered during the page refresh.
I need to trigger a method only during the tab or browser close, but not during the page refresh.
I know this question has been asked several times, some solution suggested using cookies will not be helpful in my case
navigator.sendBeacon() method can be used for sending data from browser to server when a tab is closed.
Here is an example:
window.addEventListener("unload", function informServer() {
navigator.sendBeacon("/server-api-to-collect-data", my-data)
})
More information:
https://developer.mozilla.org/en-US/docs/Web/API/Navigator/sendBeacon
As far as I know, you can not listen to actions of browser's tab close or exits. For your application it is an "unload", whatever caused it...
The only thing I could think about is maybe add a listener for keyboard key press (F5), however it doesn't help in case someone refreshed by clicking on the browser's refresh button.
I don't know what is the use case, but most of the things should be done when a page unloads (no matter why) and/or when the page is back up again. So most of the solutions are for situations where your page is loaded again - and then you can determine what was the source of the load and make farther actions, but since you have an option were someone can close and never come back, that might not be the case.
Some solutions for page load up:
You can use Navigation type.
You can check referer.
You can use cookies or other types of browser storage.
I would recommend to rethink about your use case. Maybe you can do whatever you want on load up or leave it on onBeforeUnLoad without knowing the future :)
I am making an auto-clicker for a website. Sometimes, when the element is clicked, it will navigate to a different page, presumably via document.location. I would like to prevent the redirect, and keep the user on the same page. The closest solution I've acheived so far is by using
window.onbeforeunload = function(){
return 'Are you sure you want to leave?';
};
which asks the user to confirm if they would like to remain on the page. If the user clicks cancel, then they remain on the current page, which is ideal.
The issue is that I have to manually click cancel on the prompt, which is not ideal and I don't believe I can make JavaScript auto-click cancel.
So is there a way for me to prevent the redirect, without the prompt appearing?
I figured it out. It is possible. I just need to use:
Object.freeze(document.location);
An interesting fact
It's possible to enter in any javascript to any existing webpage.
You can do this by injecting a via third party script, or just manually enter it into the inspector like this:
window.onbeforeunload = fuction () { return false;}
Websites commonly include references to third party scripts like analytics, ads, tools, libraries etc, and all of them could theoretically include a malicious script.
This is technically hijacking the existing website. It would be easy to hack peoples websites because of this, which is probably why the prompt is there as a mediating safe measure from web browsers.
Note if you close the web browser down, it won't prompt, so this method is not a fail safe anyway.
Conclusion.
No, it's not possible.
Alternative
Regarding the auto clicker redirect, why don't you simply put in an if condition that doesn't redirect them?
A website contains a "random" link, which loads a url that returns a 307 redirecting to the url we want. It works fine: click it and you load a random page. The problem is that each time you click it, the browser assumes you're loading the same page: so if you're on the homepage, then you follow the random link 5 times, then you press back, you'll be taken all the way back to the homepage, with no way to find the random pages you were just looking at. I want to modify this behavior so that users can access previous random pages via the back and forward buttons.
I don't own the website, so I can't just change the redirect code.
Here's what I've tried, all of which has failed.
Predicting what would be redirected to. While somewhat possible, there would be no way to avoid failure in up to .1% of clicks, and it would react very poorly to unexpected events, like a page that's published a day late, let alone a sit structure change.
Loading the 307 page via ajax. The request stops at readystate == 2 and I can't access the location header.
Cancel the click event and instead set location.href = random_link.href. This has no effect - the new page still doesn't go into history.
Have the new page call history.pushState. This successfully adds the page to history, but I can't find a way to distinguish between new pages and ones being opened via the back button, so the history quickly becomes very corrupted.
Keeping my own history in localStorage. As above, I can't tell when the back button is being used.
I'm working on a solution that I'm pretty sure will work, involving loading the page in an iframe over the existing page and using a background process and messaging to work around the fact that content injections from chrome extensions can't access window.parent from within iframes. And using the history API to reflect the current iframe's URL in the address bar, and get the back and forwards buttons to apply to the current iframe where appropriate.
While I'm pretty sure the last solution can be made to work, it's a hideously complex and heavyweight approach to what seems like a simple problem. So I thought I'd ask you guys before I continue: any other ideas?
Have you tried storing the locations in localStorage, then hi-jacking the back button ?
I am sure you know how localStorage works, for hi-jacking the back button you can refer to this : Is there a way to catch the back button event in javascript?
T.
i want to know is there any way we can know browser's events.. like : clicking on BACK button, FORWARD button, REFRESH button by javascript.
These specific browser events are not available as it would be vulnerable to severe privacy violations. Privacy is something browser vendors hold sacred and a key selling (proverbial) point. All browsers allow you to know is when a user enters or leaves your page for which Kamui pointed out the technical details.
Within the same site, it's possible to achieve some browser event tracking using cookies and javascript. For example track wether users click on a hyperlink and label it as a forward event and when a user leaves the page without clicking on a hyperlink it could be one of:
browser url input
back action
javascript location.href replace
The location.href replace can be tracked as well when you have full control over all javascript, just use a helper method with tracking code instead of directly chaning location.href.
That leaves browser url input and the back action. With cookies and request headers (getting the referrer) it is possible to get close to finding out the forward and back events, though not 100%, but pragmatically, 99% sure is good enough.
Figuring out the refresh event is easy with request headers (referrer), if the current url matches the referrrer, it's a refresh event.
Now I offer no code or definite solution, but I outlined what you could do to track back, forward and refresh events within a single domain context. It won't be a quick and easy way to implement it and as far as I know, there's no framework in existance that reliably tracks browser events or even comes close to what I described above.
A more common/lazy technique to achieve something similar is to create a single page app, for which there are many frameworks available. Just google single page app framework, but thats a pretty heavy solution with other implications that I won't go into now.
You can not capture (for example run some piece of code when user presses Back button) them, however, you can direct your pages in history by using:
history.go
history.back
history.forward
More about JS History object.
As #sarfraz says you cannot capture the back and forward button clicks but you could call
window.onbeforeunload = function(){alert("you just tried to leave the page");};
which should be triggered when either the back/forward/refresh buttons are clicked to perform an action, unfortunately you can't tell if they are going back or forward. Please note don't alert a message it's really annoying when trying to exit a page.
EDIT
you can also do this in jQuery if you have it
$(window).unload( function () { alert("Bye now!"); } );
Suppose I have a page open in a browser and I go to my address bar and enter another page. Then I hit the back button to go to my original page. I'd like to write some Javascript code that can detect this scenario and respond to it.
As best I can tell neither the ready event, the onload, nor any inline Javascript on the page itself is re-executed in this scenario. Is there anything else I can do?
Cross-browser support is important here. jQuery based solutions preferred but not required.
Edit for clarity: the navigation I'm assuming is Page A -> Page B -> back to page A where I'm assuming that Page B may or may not be under my control.
You should try to give the user a cookie on both pages, the navigated to page and the page itself, with dates and times and compare see if they're close, or if they show that he's been on one page, been on another, and then redirected.
Another option is to give the user a cookie when he is redirected
In Firefox, you can check for the DomContentLoaded event. For a cross-browser solution, a little more work is required:
http://dean.edwards.name/weblog/2005/09/busted/