Develop Reference

Alert box after redirect

so i know this may sound stupid, but I want to know if there is any way that i could redirect someone to a website, and then display an alert box on the web page, using either javascript or any other interface that can be weaved into HTML5. I asked some of my classmates, and they didn't know, so I just need a confirmation that this isn't possible.
I have ran a few trials i found, but on further review, they wouldn't work.
edit I have control over the site, but I wish for the box to only pop up if i redirect it.
I can give the code if it would help, but I'm doubtful it will help
sorry for wasting your time if i did. thanks.

Similar to Gerard's answer, but using query strings. A possibly more standard solution.
On the first page:
<script>
window.location = 'https://{your website here}/?showAlert=true';
</script>
Then on the 2nd page.
const urlParams = new URLSearchParams(window.location.search);
const showAlert = urlParams.get('showAlert');
if(showAlert === "true") {
alert("Hello");
}
Note this will not work in internet explorer

You could communicate to the new site that it's a redirect by appending the route:
On the site you want to redirect from:
<script>
// if you can't use a normal link, change the url with JS
window.location = 'https://{your website here}/#redirect';
</script>
On the site you want to show the alert:
<script>
if (window.location.pathname.includes('#redirect') alert('What you want to say');
</script>
If you only have control over the first site, you could alert before redirecting, there wouldn't be much difference to the user since the alert blocks execution of other code.

You can call an alert box in a HTML document with JavaScript like this:
window.onload = function () {
alert("Hello World!");
}
-> https://jsfiddle.net/u8x6s31v/
You can also redirect somebody, if the page he's visiting is yours. Is that what you mean?
Update:
I think you can't see the URL where someone comes from with JavaScript. The only way to trigger scripts for some people is to add a hash.
window.onload = function () {
hashUrl = window.location.hash;
if (hashUrl == "#alert") {
alert("Hello World!");
}
}
Then call for example: domain.tld/path/index.html#alert
-> https://jsfiddle.net/u8x6s31v/1/

This is a vague questions with a lot of possible answers but seeing as how you're new, I'm going to speculate on what you might be asking and try to answer it.
It's not clear what you mean by "redirect".
Is this a server-side redirect like when you move/change a URL and you redirect the old URL to a new URL? Is this a Javascript meta refresh that you put in a 404 template? Is this a redirect that occurs after a user takes an action?
Regardless, you're going to have to "annotate" that user and then take action upon that annotation. The most obvious method would be based on the "referrer" HTTP header but it is also possible to do it based on the presence of a cookie.
Additionally, adding URL parameters to a redirect is trivially easy and often used for stuff like this.
The immediate things that come to my mind would be via Google Analytics (preferably implemented via Google Tag Manager because it'll make it easier).
Look into "outbound link tracking", "cross-domain tracking" and "UTM campaign tracking" (all related to Google Analytics and/or Google Tag Manager) and you'll probably find something that suits your needs.
URL shorteners are commonly used to mask parameters in links and there are open source libraries that allow you to host your own URL shortener (which you could integrate into your redirects) or do some other type of link tracking like is often used for affiliates.

Javascript "link" should not load

I know it sounds weird, but i need to make that…
So I have this function, that activates onClick.
function opensite() { location.href='https://www.site.com/'; }
Is there a way to open that url, but not load it?
So your browser will say something like "page not found/server down/no internet connection"…
Is it possible and how ? My server can use every language … (JS,JQUERY,PHP,HTML…)
Why I should do this ? Long story, please don't ask about ;)
Thank you
Evert
*EDIT*
I have a script that perfectly works without internet connection because it doesn't load the page in the 'link'… I'm trying to make this also work WITH internet connection...

Are you looking for this?
window.open('http://www.site.com/')
But some browser will block the pop-up window. There's also another way:
var a = document.createElement('a');
a.href = 'http://www.site.com/';
a.target = '_blank';
a.click();
to emulate a click on a link.

If you own the site you are trying to make appear offline, then the easiest way is to upload an index.html containing the error you are trying to display.
But really, no. This is not possible.
I am assuming you do not own the other site, and due to security reasons, browsers block this type of behavior. Since you are asking to bypass security settings, and telling us "don't ask" I can only assume you are trying to steal peoples identities.
No matter how bad you need this to work, it wont. Stop trying.
Edit:
If you simply do not want your website to follow a click, then I would use e.preventDefault() in your jQuery event handler

load page and execute javascript in a url

Hello wonderful stackoverflow users.
I have a question about url loading.
In many browsers and web viewers, there is the functionality to load a url to a website, but also a url to execute javascript.
Load a website: http://www.google.com
Load a script: javascript:alert("Hello!");
My question is, is there a way to load an http request as well as a javascript.
The answer is most likely no, but I want to confirm because I can't find any resources that describe this.
I was thinking it would be something like:
http://www.google.com&&javascript:alert("Hello!");
but the problem is, of course, this is not correct.
The reason why I am doing this is to provide a url that once it is clicked, it will also execute a certain javascript function. This will be in Android.
I appreciate any response, and understand that the answer may be no.

It all depends on whether you have control of the page being linked to. If you cannot modify the source of the linked page, then the answer is quite simply, no.
But, if it is your page, you can pass arguments in the hash, and then read the hash when the page loads and execute script accordingly.
window.onload = function () {
if (location.hash.indexOf("doSomething") > -1) {
// do something
}
};

You can execute javascript when a page loads using Browser plugins, such as GreaseMonkey for Firefox, or TamperMonkey for Chrome.
https://addons.mozilla.org/en-us/firefox/addon/greasemonkey/
http://tampermonkey.net/index.php?version=3.11&ext=dhdg&updated=true

Bookmarklet window.open blocked by most browsers, delicious/tumbler's does not

Hey guys --
The website I'm working on requires a bookmarklet launchable from your bookmark toolbar.
I've noticed that some browsers are blocking my bookmarklet.
However, similar bookmarklets such as Tumblr's, Twitter's, and Delicious' have workarounds where their bookmarklet pages are not getting blocked.
My current launch script looks like:
javascript:void(window.open(%22http://mywebsite.com/share/form?
u=%22+encodeURIComponent(location.href)+%22
&t=%22+encodeURIComponent(document.title),
%xz%22,%22status=0,toolbar=0,location=0,menubar=0,resizable=false,scrollbars=false,height=379,width=379%22));
It's a simple window.open, which is clearly not enough to handle certain exceptions
The sites, below is Delicious' launch script, all seem to have workarounds that look very similar to that of below:
javascript:(function(){
f='http://www.delicious.com/save
?url='+encodeURIComponent(window.location.href)+
'&title='+encodeURIComponent(document.title)+
'&notes='+encodeURIComponent(''+(window.getSelection?window.getSelection():document.getSelection?document.getSelection():document.selection.createRange().text))+
'&v=6&';
a=function(){
if(!window.open(f
+'noui=1&jump=doclose','deliciousuiv6','location=yes,links=no,scrollbars=no,toolbar=no,width=550,height=550'))
location.href=f+'jump=yes'};
if(/Firefox/.test(navigator.userAgent))
{setTimeout(a,0)}else{a()}})()
It seems like they append some extra GET parameters to the URL if the user agent is firefox.
I'm assuming then, if that is the case, that the init scripts on the actual page loading from the bookmarklet handles this exception somehow?
Has anyone had any experience with this issue? Would you be able to point me to any resources or tips? I have been stuck with this roadblock for sometime now.
Thanks in advance

the delicious bookmark does not directly invoke the window.open() - it creates a function (called a in there) which is then executed in a setTimeout(a,0) for firefox (i assume the problem you have is in firefox).
You can try a similar method, and see if it works for you.

How do I refresh/reload a Chrome Extension?

I'm developing an extension in Chrome 4 (currently 4.0.249.0) that will show the user's StackOverflow/SuperUser/ServerFault reputation in the status bar. I've designed an options page to get the user's profile IDs and I save them to localStorage and read them well in the extension. It all works great.
The problem is I cannot find a (programmatic) way to refresh the extension upon options saving. I tried calling location.reload(); from the extension page itself upon right clicking it - to no avail. I pursued it further and tried looking at what Chrome's chrome://extensions/ page does to reload an extension, and found this code:
/**
* Handles a 'reload' button getting clicked.
*/
function handleReloadExtension(node) {
// Tell the C++ ExtensionDOMHandler to reload the extension.
chrome.send('reload', [node.extensionId]);
}
Copying this code to my event handler did not help (and yes, I tried replacing [node.extensionId] with the actual code). Can someone please assist me in doing this the right way, or pointing me at a code of an extension that does this correctly? Once done, I'll put the extension and its source up on my blog.

Now the simplest way to make extension to reload itself is to call chrome.runtime.reload(). This feature doesn't need any permissions in manifest.
To reload another extension use chrome.management.setEnabled(). It requires "permissions": [ "management" ] in manifest.

window.location.reload() works for me
I am using chromium 6.x so it might be fixed in newer version

The chrome.send function is not accessible by your extension's javascript code, pages like the newtab page, history and the extensions page use it to communicate with the C++ controller code for those pages.
You can push updates of your extension to users who have it installed, this is described here. The user's application will be updated once the autoupdate interval is hit or when they restart the browser. You cannot however reload a user's extension programmatically. I think that would be a security risk.

I just had this same problem with an extension.
Turns out you can listen for storage changes within background.js using chrome.storage.onChanged and have that perform the refresh logic.
For example:
// Perform a reload any time the user clicks "Save"
chrome.storage.onChanged.addListener(function(changes, namespace) {
chrome.storage.sync.get({
profileId: 0
}, function(items) {
// Update status bar text here
});
});
You could also reload parts of your extension this way by taking the changes parameter into account. chrome.runtime.reload() might be easier, but this has less overhead.

For all future Googlers - the Browser Extension spec now includes runtime.reload() - https://developer.mozilla.org/en-US/docs/Mozilla/Add-ons/WebExtensions/API/runtime/reload
For Chrome, you might need to use chrome.runtime.reload() (but I'd handle such cases via Mozilla's awesome webextension-polyfill).