In javascript functions can be overwritten. You can simply assign it a new purpose: window.onbeforeunload = function () { // blank function do nothing } This will completely overwrite the existing version of window.onbeforeunload. Note: Why don’t you simply remove the line of code that sets this function in the first place? Or if you … Read more
Thank you for your replies! It turns out I was completely wrong about this being a browser issue – the problem was on the server. ASP.NET serializes requests of the same session that require session state, so in this case, the next page didn’t begin processing on the server until those ajax-initiated requests completed. Unfortunately, … Read more
window.onbeforeunload = function() { return ‘You have unsaved changes!’; } See the MSDN article on onbeforeunload Also there is a similar question in SO
From the Mozilla Developer Network page: When this event returns a non-void value, the user is prompted to confirm the page unload. This means the return value of the handler must be undefined (not ”, false, or null) in order to avoid triggering the confirmation prompt. window.onbeforeunload = function() { $.post(“track.php”, { … }); return … Read more
Call unbind using the beforeunload event handler: $(‘form#someForm’).submit(function() { $(window).unbind(‘beforeunload’); }); To prevent the form from being submitted, add the following line: return false;
Short answer: You can’t. Longer answer: For rather obvious “security” reasons it is very limited what you can do when a user tries to navigate away from a page / close a tab or in any other way leave the site. The reason is that browsers want to make absolutely sure that you cannot prevent … Read more
You can do it like this: $(function() { $(window).bind(‘beforeunload’, function() { setTimeout(function() { setTimeout(function() { $(document.body).css(‘background-color’, ‘red’); }, 1000); },1); return ‘are you sure’; }); }); The code within the first setTimeout method has a delay of 1ms. This is just to add the function into the UI queue. Since setTimeout runs asynchronously the Javascript … Read more
I found a workaround for Firefox with setTimeout function because it does not have the same behaviour as other web browsers. window.onbeforeunload = function (e) { var message = “Are you sure ?”; var firefox = /Firefox[\/\s](\d+)/.test(navigator.userAgent); if (firefox) { //Add custom dialog //Firefox does not accept window.showModalDialog(), window.alert(), window.confirm(), and window.prompt() furthermore var dialog … Read more
Using the form’s submit event to set a flag might work for you. var formHasChanged = false; var submitted = false; $(document).on(‘change’, ‘form.confirm-navigation-form input, form.confirm-navigation-form select, form.confirm-navigation-form textarea’, function (e) { formHasChanged = true; }); $(document).ready(function () { window.onbeforeunload = function (e) { if (formHasChanged && !submitted) { var message = “You have not saved … Read more
I would guess that they are using the History API. By listening to popstate window.addEventListener(“popstate”, function(e) { … }); you can show a warning before allowing doing anything stupid.