I was having many problems trying to find the reason of why my ajax function was not working on Safari, Chrome and sometimes Firefox, but worked very well on IE. I made a little change, and everything start working perfect (in every browser), but I still dont know why, and I want to find out the main reason of this.
I had an Ajax function respuestas() which insert some data on a database. This function is called by some links like this: <a onclick="respuestas()" href="link.html">LINk </a>. So when I click on the link, the function takes the proper information and inserts it on the database and then go to link.html. Again, this only worked for IE.
I insert an alert(xml.responseText) to see the response that i was having. Safari, fireforx and chrome returns an empty alert.
I was tired of changing pages everytime I wanted to test my function, so I add a button calling my function (without going to another webpage) and IT WORKED!. Now, I have something like this: <a onclick="respuestas()" href="#">LINK </a> and put window.location.href="link.html" inside my ajax function, so the change of pages occur after the ajax response is completed, and it is working very well.
But I do not entirely understand why this works and the other way does not.
This because the link element has also it's default listener. So, to prevent any extra action on click, you should prevent default action. The simple way to do this is to return false on click.
<a onclick="respuestas(this); return false;" href="link.html">LINk</a>
And your respuestas in easiest way should be like this:
function respuestas(link) {
/* do what you need here */
window.location.href = link.href;
}
This is pretty primitive, but I believe you'll get the idea.
What's happening here is that your browser was navigating to the next page before repusetas() was able to execute. In order to ensure that your script is going to fire before the browser follows the link, you need to take control of the click event. In jQuery it works like this:
$('a').bind( 'click', function( event ){
event.preventDefault();
repuestas();
var href = $(this).attr('href');
window.location.href = href;
});
Try this Jquery code
function respuestas()
{
$.ajax({
type: "post",
url: "insert.php?data="+data,
success : function(data){
window.location.href="link.html";
},
error : function(){
alert("Could not ");
}
});
}
Related
I have script, what work one time when window loaded, it work on this page, but site use some navigation links what not fully reload page (see this answer for example: Modify the URL without reloading the page). How can I detect that and run my script again?
I have one idea: storing URL (without anchor) in variable and check it periodically with current url, but I think this is bad solution. May be you know better one?
JavaScript or JQuery is possible to use.
Use window.onpopstate or window.onpushstate if u are using pushState or replaceState ( from ur given example).
ex:-
To Navigate Without reload ( you already did this )
// Your code to fetch new URL body and title
// update the DOM then use following code to update URL also (don't use location.href, otherwise the page reloads)
// sorry u already know this because u provided the example ;)
let data = { title : "Current Title",
body : document.body.innerHTML" } // to store current page data
window.history.pushState(data, 0, "newURL");
To detect navigation ( i.e., you wanna do )
window.onpushstate: when above code runs for navigation to a new url and load new content without reload ...
window.onpushstate(function() {
// detects ur navigation
})
window.onpopstate: when you press back button
window.onpopstate(function (e) {
let { data } = e.state;
// data object that u gave in pushState method when u called ur last / latest pushState method...
// use this data to retrieve previous data content and title
let { title, body } = data;
document.title = title;
document.body.innerHTML = body
})
for more detail mdn docs
That's because the new pages are either
1 ) Already at the ready and simply being brought in-sight by jQuery
2 ) Ajax called in.
If you scout for your navigation (the links you click on to go to the other page), you should find click me or so.
If you look for wherever this is is bound (i.e.: $('#navigation a').on("click", function(){});, you can simply wrap your script within a function, and trigger this function together with loading the new page every time. (after it, obviously).
I wish I could be more clear, but you did not provide any code yourself, so I have absolutely no idea of what kind of example I should be giving here.
-- the point: Those page changes are triggered by something in your javascript. Find the trigger that makes the page-change happen, and simply insert myCustomFunction();.
If you want to make your bindings update with a new DOM, you could use this:
function setBindings(){
//removing the old bindings prevents the "click" from triggering twice.
$('a').off("click");
$('a').on("click", function(){
//load page and such here
//Apply script you want to run here
setbindings(); //rerun the function to set the bindings.
});
}
I think you are looking for hashchanges you can listen to this event onhashchange
window.onhashchange = function(e) {
var sublink = window.location.hash.substring(1);
//do your thing here
}
You can also check what updated the url after the hashchange
var sublink = window.location.hash.substring(1);
I think the URL of script is cached，do you used Ajax get method？if it is，please
like this write url "wwww.baidu.com?"+Math.random();if not is ,in the firefox ,you can used pageshow event.
I am working on a site that has multiple links to other sites. What I want is to send an ajax call to report that the user is going away when someone clicks and navigates away from the page. I put an alert on click of the links, which works but for some reason the controller never gets the ping.
Any assistance will be appreciated on how to achieve it.
Can't be done.
When you go to navigate away, there is only one event that can catch that, the onbeforeunload event, and that is quite limited in what it can do.
Not to mention there are other ways of leaving the page without navigating away:
Losing network connection
Closing the browser.
Losing power.
The only thing you can do is to set up a heartbeat kind of thing that pings the server every so many milliseconds and says 'I'm Alive.'
Depending on what you are trying to do, there is usually a better option, however.
You can try to simply set click event handler which will check the href attribute of every link before navigating. If it goes to another website, the handler sends AJAX request and then (after server responding) redirects to the page.
var redirect = '';
$('a').click(function() {
if (this.href.host != document.location.host) {
if (redirect) return false; // means redirect is about to start, clicking other links has no effect
redirect = this.href;
$.ajax({
url: '/away',
success: function(){document.location.href = redirect;}
});
return false;
});
However it can't work properly, if user has opened your page in multiple tabs.
The only reliable way to do this these days is by hooking (i.e. add event listener) your code in so called sendBeacon method from Beacon API on beforeunload event (i.e. when user tries to navigate away from page).
The navigator.sendBeacon() method asynchronously sends a small amount of data over HTTP to a web server. It’s intended to be used for sending analytics data to a web server, and avoids some of the problems with legacy techniques for sending analytics, such as the use of XMLHttpRequest:
<script>
var URL = 'https://your.domain/your-page.php';
// on 'beforeunload'
window.addEventListener('beforeunload', function (event) {
navigator.sendBeacon(URL);
// more safely is to wait a bit
var wait_until = new Date().getTime() + 500;
while (new Date().getTime() <= wait_until);
});
</script>
You can try:
$(window).on('beforeunload', function(){
return "This should create a pop-up";
});
You can achieve it by capturing clicks on all the links on the page (or all the relevant links) and then call ev.preventDefault() on it to prevent the browser from navigating directly to that page.
Instead, you can make an AJAX call to your server and when that call returns, you can set window.location to the URL the user was trying to navigate to.
Here is a workaround you could try.
At the loading of the page, use jquery to move all href attributes to tempHref attribute. Then, attach a method to catch the click event.
This way, clicking on the links will not automatically move to the intended destination.
When the click occurs, simply perform the ajax call, and then using javascript, move to the other page.
$('a').each(function () {
var link = $(this);
link.attr('tempHref', link.attr('href'));
link.removeAttr('href');
});
$(document).on('click', 'a', function ()
{
//perform ajax call;
location.href = $(location).attr('tempHref');
});
A page source snippet has the HTML:
Next
I know that the "#" is a placeholder that is handled by Javascript on the page. I believe the relevant Javascript snippet is:
function changepage(start) {
makerequest('/ajax/inventory_search.php', collectformvalues(start));
}
// do not flash the search options when using next/prev - just when the search is changed
function changepageforpagerlink(start) {
doEffectOnAjax = false;
changepage(start);
return false;
}
I need to know if there is a way that I can submit a URL and have the next page's page source returned. Is there a URL that is submitted at all in the above example?
My environment is VBA. I'm not using a browser, just communicating with the server. One thing I thought of is to mimic the "makerequest" function, but I don't know how to do that or if would even work. I know at the heart it's all just sending text to the server and receiving text back so I would think there is a way. . .
Bottom line is that I need to access the page source from the next page via VBA and not using a browser.
you can use JQuery to achieve this:
function changepage(start) {
makerequest('/ajax/inventory_search.php', collectformvalues(start));
}
changes to
function changepage(start) {
$.ajax({
type:POST,
url:"/ajax/inventory_search.php",
}).done(function(){
//do anything when it's done.
});
}
I have a below anchor as below
<a onclick="return getFile('/log/sample.log');" href="/log/sample.log" target="_blank"> sample.log </a>
Because at my server, the log directory in href may be not correct. So the function "getFile" would change the href to the correct one after asking the server.
The first click always failed since the link was not correct, then after AJAX process in getFile was finished and the correct href was given, the clicks later on was ok.
The problem is how I forcefully let html wait ever at the first click until the href is changed, then do the query on the server.
Thanks in advance.
I guess my current way could be not in the correct direction by using "onclick" to implement the idea.
You want something like this
$(function() {
//assume you tagged all anchors you want to do this for with class=adjustlink
$('a.adjustlink').click(function(e) {
var thisAnchor = $(this); //save reference for later use
//this will either be true (see below) or undefined (falsy)
if(thisAnchor.data('myapp.linkHasBeenTested')) {
return; //continue on
}
// Stop the link from being navigated (the default for this event)
e.preventDefault();
//I'm assuming this is fetched as text but could just as well be JSON or anything else
$.get('/LinkAdjustment/', thisAnchor.attr('href')).done(function(result) {
thisAnchor.attr('href', result); //set the href
thisAnchor.data('myapp.linkHasBeenTested', true);
thisAnchor.trigger('click');
});
});
});
As an interesting side-note. You might be attempting to do something similar to the way REST is intended to be done. You might consider, first fetching a resource that will tell you up-front what the correct links are.
I would recomend setting the href to # initially. And in your getFile, set the href to the correct value and then programatically click the 'a' on success of your ajax
You will need to find the element to do this. It can either be done by setting an id and then using document.getElementById(), or would be easier to do do this using Jquery selectors, and it even has a .click() you can call after.
If you want persist with this flow make your ajax call synchronous, it will forcibly wait.
But this flow is not suggested, I would have rather updated these hrefs on page load or would have set a default url to my server page, which would then redirect to right log file
I want to send an ajax request when a user leaves a page or closes the window.
Here is my code inside :
<script type="text/javascript">
function sendajax(){
$.ajax({
url: "someurl",
data: mydata,
async : false
});
}
</script>
<script type="text/javascript">
window.onbeforeunload=function(){sendajax();};
</script>
When the event occurs the event fires twice.
Why does in happen?
I know I can prevent it by adding a variable var ajaxSent=true; but may be there is a cleaner way to do it?
UPD:
I replaced the sendajax function content with some other code (without sending ajax) and found out that ajax is not the one causing the problem. It still enters the function twice.
Based on the code in your edit and comments, it looks like it could simply be caused by the broken link you are clicking to leave the page.
Given the following code:
<script>
function doSomething() { console.log('onbeforeunload fired'); }
window.onbeforeunload = doSomething;
</script>
link A
link B
If I click on link A, I get two console log entries, if I click on link B I only get one.
It looks like it could be a quirk of how the browsers handle their internal "This web page has not been found" pages, causing your page to be refreshed and closed again before showing the message, leaving you with two occurrences of the onbeforeunload event.
I had the same problem and it took a while to understand and resolve, sharing the case details:
There was a custom JS within our template that manipulated the menu.
It caused the unload to fire twice, only when clicking on the menu links, not on other links, and only in IE/EDGE.
We eventually stopped the propagation on these links and the problem was resolved.
$('.SELECTOR a[href^="http://"]').on('click', function(e){
e.stopPropagation();
});
It's a specific bug in your application, therefore you won't find too much information on google.
You could try the following code:
<script type="text/javascript"><br>
window.onbeforeunload=function sendajax(){<br>
$.ajax({<br>
url: "someurl",<br>
data: mydata,<br>
async : false<br>
});<br>
};<br>
</script>
or you can define sendajax() {} at some place and the use it like onbeforeunload = "sendajax()" not as onbeforeunload = "function () { sendajax() }"
beforeUnload is cancellable
I know this post is quite old but from the Chrome Pagelifecycle API documentation, browsers can occasionally partially unload pages to save resources. https://developers.google.com/web/updates/2018/07/page-lifecycle-api beforeUnload is not reliable to make sure that the page is closed. This especially happens on android devices when the screen is locked.
There is a jsfiddle that I found somebody wrote that you can test out https://jsfiddle.net/ov6b9pdL/. Keep the screen locked for 5-10 minutes on Chrome android and you'll see that beforeUnload is fired without even closing the tab.
$(document).ready(function() {
window.addEventListener('beforeunload', showLoader);
});
var showLoader = function() {
$('#loader').show();
};
Agree with AlonMichaeli's concept.
In my application there was anchor tag wrapped with in a div together with couple of spans. When Anchor was clicked on a dirty page, there was couple of 'Leave site' notifications.
It worked fine if any other part of menuItem (div or spans) are clicked.
So in custom javascript method I've added stopped propagation and preventDefault only if anchor tag is clicked. Somehow in this case preventDefault is necessary.
function menuItemClicked(event: JQueryEventObject) {
var item = $(event.target);
if (item.is(".anchor-item")) {
event.stopPropagation();
event.preventDefault();
}
href = item.closest(".anchor-item").attr("href");
if (!event.ctrlKey && href) {
window.location.href = href;
}
}