Related
I have this HTML toggle button for my menu:
<a href="#" id="toggle_nav" class="sidebar-toggle" data-toggle="offcanvas" role="button">
How can i save the toggle state to reload it on page load
I have started off with:
$(document).ready(function() {
$("#toggle_nav").toggle(function() {
});
});
but im not sure what to use to keep the state
Like people are saying in the commends you can use html 5 web storage.
You have 2 types:
- localStorage - stores data with no expiration date
- sessionStorage - stores data for one session
how to set:
localStorage.setItem("name", "value");
How to get the value
localStorage.getItem("name");
So now can you do a simple check like:
if (localStorage.getItem("toggle") === null) {
//hide or show menu by default
//do not forget to set a htlm5 cookie
}else{
if(localStorage.getItem("toggle") == "yes"){
//code when menu is visible
}else{
//code when menu is hidden
}
}
More information here
Use a hidden field. Use JS to set this hidden field value whenever the panel is opened or closed, and to check the hidden field on pageload.
Example-
In your JS, I use one function to set which panels are open/closed and a 2nd to arrange them. This example is based on having multiple panels on your page but you can quickly change it to handle just one panel if needed.
function init() {
if ($("#hdnOpenPanels").val()) {
$(".fixPanels").click();
}
}
// Ensures that the correct panels are open on postback
$(".checkPanels").click(function () {
var checkPanel1= $("#Panel1").hasClass("in");
var checkPanel2 = $("#Panel2").hasClass("in");
var checkPanel3 = $("#Panel3").hasClass("in");
$("#hdnOpenPanels").val(checkPanel1 + "|" + checkPanel2 + "|" + checkPanel3);
});
$(".fixPanels").click(function () {
if ($("#hdnOpenPanels").val().split('|')[0] === "true") {
$("#Panel1").collapse('show');
} else {
$("#Panel1").collapse('hide');
}
if ($("#hdnOpenPanels").val().split('|')[1] === "true") {
$("#Panel2").collapse('show');
} else {
$("#Panel2").collapse('hide');
}
if ($("#hdnOpenPanels").val().split('|')[2] === "true") {
$("#Panel3").collapse('show');
} else {
$("#Panel3").collapse('hide');
}
});
Now you have two easy classes available to add to any items that will require the page to know which panels are open (.checkPanels) and also to "fix" which panels should be open (.fixPanels). If you have modals on the page they'll need to "fixPanels" when they closed (even though there may not have been a postback).
On your code-behind:
Add this to your PageLoad:
protected void Page_Load(object sender, EventArgs e)
{
if (Session["sPanels"] != null)
{
hdnOpenPanels.Value = Session["sPanels"].ToString();
Session.Remove("sPanels");
}
if (IsPostBack){...}
else {...}
}
Finally, on any code-behind functions that will be causing a post-back affecting the panels, add this line at the bottom of the function(s):
Session["sPanels"] = hdnOpenPanels.Value;
There are any number of ways to accomplish this, including local storage, cookies, URL parameters, anchor fragments, and server-side storage.
If you need to persist the value for a user, regardless of browser, you'll need to store it on the server side as a user preference against an identified user's profile.
If you need to persist against a single browser instance, regardless of user, you can use a client-side solution like localStorage (for persistence across browser sessions) sessionStorage (for persistence within a single browser session) or cookies (which can be configured to do either).
For example, here is a solution that uses localStorage to persist the state of a toggle across page reloads and browser sessions.
This code does not run in an SO snippet, so see this Fiddle for a demo.
Javascript
var menuStateKey = "menu.toggle_nav.state";
$(document).ready(function() {
var $nav = $("nav");
var setInitialMenuState = function() {
// Note: This retrieves a String, not a Boolean.
var state = localStorage.getItem(menuStateKey) === 'true';
setNavDisplayState(state);
};
var toggleNav = function() {
var state = $nav.is(':visible');
state = !state;
localStorage.setItem(menuStateKey, state);
setNavDisplayState(state);
};
var setNavDisplayState = function(state) {
if (state) {
$nav.show();
} else {
$nav.hide();
}
};
$("#toggle_nav").click(toggleNav);
setInitialMenuState();
});
HTML
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<nav>I am the nav</nav>
Toggle
You can extent toggle
$.prototype._toggle = $.prototype.toggle;
$.prototype.toggle = function() {
// save to localStorage
$.prototype._toggle.call(this)
}
And write code that use localStorage to start toggle
You can store toggle state in localStorage object.
// Check browser support
if (typeof(Storage) != "undefined") {
// Store
localStorage.setItem("toggleState", value);
// Retrieve
localStorage.getItem("toggleState");
} else {
"Sorry, your browser does not support Web Storage...";
}
Check out Local Storage - Dive Into HTML5
There are JQuery plugins available to facilitate this.
$.localStorage;
storage=$.localStorage;
storage.set('foo','value');
storage.get('foo');
Read more at Jquery Storage API.
Cheers !
As others explained we can use localStorage(HTML5) or else we can use cookies
Please refer this article on how to persist the data using cookies.
As this implementation requires less data to be stored in cookie. Using cookie would be the good approach for your implementation.
I am writing an iframe based facebook app. Now I want to use the same html page to render the normal website as well as the canvas page within facebook. I want to know if I can determine whether the page has been loaded inside the iframe or directly in the browser?
Browsers can block access to window.top due to same origin policy. IE bugs also take place. Here's the working code:
function inIframe () {
try {
return window.self !== window.top;
} catch (e) {
return true;
}
}
top and self are both window objects (along with parent), so you're seeing if your window is the top window.
When in an iframe on the same origin as the parent, the window.frameElement method returns the element (e.g. iframe or object) in which the window is embedded. Otherwise, if browsing in a top-level context, or if the parent and the child frame have different origins, it will evaluate to null.
window.frameElement
? 'embedded in iframe or object'
: 'not embedded or cross-origin'
This is an HTML Standard with basic support in all modern browsers.
if ( window !== window.parent )
{
// The page is in an iframe
}
else
{
// The page is not in an iframe
}
I'm not sure how this example works for older Web browsers but I use this for IE, Firefox and Chrome without an issue:
var iFrameDetection = (window === window.parent) ? false : true;
RoBorg is correct, but I wanted to add a side note.
In IE7/IE8 when Microsoft added Tabs to their browser they broke one thing that will cause havoc with your JS if you are not careful.
Imagine this page layout:
MainPage.html
IframedPage1.html (named "foo")
IframedPage2.html (named "bar")
IframedPage3.html (named "baz")
Now in frame "baz" you click a link (no target, loads in the "baz" frame) it works fine.
If the page that gets loaded, lets call it special.html, uses JS to check if "it" has a parent frame named "bar" it will return true (expected).
Now lets say that the special.html page when it loads, checks the parent frame (for existence and its name, and if it is "bar" it reloads itself in the bar frame. e.g.
if(window.parent && window.parent.name == 'bar'){
window.parent.location = self.location;
}
So far so good. Now comes the bug.
Lets say instead of clicking on the original link like normal, and loading the special.html page in the "baz" frame, you middle-clicked it or chose to open it in a new Tab.
When that new tab loads (with no parent frames at all!) IE will enter an endless loop of page loading! because IE "copies over" the frame structure in JavaScript such that the new tab DOES have a parent, and that parent HAS the name "bar".
The good news, is that checking:
if(self == top){
//this returns true!
}
in that new tab does return true, and thus you can test for this odd condition.
The accepted answer didn't work for me inside the content script of a Firefox 6.0 Extension (Addon-SDK 1.0): Firefox executes the content script in each: the top-level window and in all iframes.
Inside the content script I get the following results:
(window !== window.top) : false
(window.self !== window.top) : true
The strange thing about this output is that it's always the same regardless whether the code is run inside an iframe or the top-level window.
On the other hand Google Chrome seems to execute my content script only once within the top-level window, so the above wouldn't work at all.
What finally worked for me in a content script in both browsers is this:
console.log(window.frames.length + ':' + parent.frames.length);
Without iframes this prints 0:0, in a top-level window containing one frame it prints 1:1, and in the only iframe of a document it prints 0:1.
This allows my extension to determine in both browsers if there are any iframes present, and additionally in Firefox if it is run inside one of the iframes.
I'm using this:
var isIframe = (self.frameElement && (self.frameElement+"").indexOf("HTMLIFrameElement") > -1);
Use this javascript function as an example on how to accomplish this.
function isNoIframeOrIframeInMyHost() {
// Validation: it must be loaded as the top page, or if it is loaded in an iframe
// then it must be embedded in my own domain.
// Info: IF top.location.href is not accessible THEN it is embedded in an iframe
// and the domains are different.
var myresult = true;
try {
var tophref = top.location.href;
var tophostname = top.location.hostname.toString();
var myhref = location.href;
if (tophref === myhref) {
myresult = true;
} else if (tophostname !== "www.yourdomain.com") {
myresult = false;
}
} catch (error) {
// error is a permission error that top.location.href is not accessible
// (which means parent domain <> iframe domain)!
myresult = false;
}
return myresult;
}
Best-for-now Legacy Browser Frame Breaking Script
The other solutions did not worked for me. This one works on all browsers:
One way to defend against clickjacking is to include a "frame-breaker" script in each page that should not be framed. The following methodology will prevent a webpage from being framed even in legacy browsers, that do not support the X-Frame-Options-Header.
In the document HEAD element, add the following:
<style id="antiClickjack">body{display:none !important;}</style>
First apply an ID to the style element itself:
<script type="text/javascript">
if (self === top) {
var antiClickjack = document.getElementById("antiClickjack");
antiClickjack.parentNode.removeChild(antiClickjack);
} else {
top.location = self.location;
}
</script>
This way, everything can be in the document HEAD and you only need one method/taglib in your API.
Reference: https://www.codemagi.com/blog/post/194
I actually used to check window.parent and it worked for me, but lately window is a cyclic object and always has a parent key, iframe or no iframe.
As the comments suggest hard comparing with window.parent works. Not sure if this will work if iframe is exactly the same webpage as parent.
window === window.parent;
Since you are asking in the context of a facebook app, you might want to consider detecting this at the server when the initial request is made. Facebook will pass along a bunch of querystring data including the fb_sig_user key if it is called from an iframe.
Since you probably need to check and use this data anyway in your app, use it to determine the the appropriate context to render.
function amiLoadedInIFrame() {
try {
// Introduce a new propery in window.top
window.top.dummyAttribute = true;
// If window.dummyAttribute is there.. then window and window.top are same intances
return !window.dummyAttribute;
} catch(e) {
// Exception will be raised when the top is in different domain
return true;
}
}
Following on what #magnoz was saying, here is a code implementation of his answer.
constructor() {
let windowLen = window.frames.length;
let parentLen = parent.frames.length;
if (windowLen == 0 && parentLen >= 1) {
this.isInIframe = true
console.log('Is in Iframe!')
} else {
console.log('Is in main window!')
}
}
It's an ancient piece of code that I've used a few times:
if (parent.location.href == self.location.href) {
window.location.href = 'https://www.facebook.com/pagename?v=app_1357902468';
}
If you want to know if the user is accessing your app from facebook page tab or canvas check for the Signed Request. If you don't get it, probably the user is not accessing from facebook.
To make sure confirm the signed_request fields structure and fields content.
With the php-sdk you can get the Signed Request like this:
$signed_request = $facebook->getSignedRequest();
You can read more about Signed Request here:
https://developers.facebook.com/docs/reference/php/facebook-getSignedRequest/
and here:
https://developers.facebook.com/docs/reference/login/signed-request/
This ended being the simplest solution for me.
<p id="demofsdfsdfs"></p>
<script>
if(window.self !== window.top) {
//run this code if in an iframe
document.getElementById("demofsdfsdfs").innerHTML = "in frame";
}else{
//run code if not in an iframe
document.getElementById("demofsdfsdfs").innerHTML = "no frame";
}
</script>
if (window.frames.length != parent.frames.length) { page loaded in iframe }
But only if number of iframes differs in your page and page who are loading you in iframe. Make no iframe in your page to have 100% guarantee of result of this code
Write this javascript in each page
if (self == top)
{ window.location = "Home.aspx"; }
Then it will automatically redirects to home page.
When writing a Chrome extension, given a tab, how can I get the URL of the previously-visited page in that tab? i.e. the url that will appear in the omnibar after I hit "back"?
Since I could not find any API approach, I just applied vux777's suggestion above: every time a page loads I store a mapping from its id to its URL. Then when I want to find the previous page of a tab, I can search for it there.
So, storage:
chrome.webNavigation.onCommitted.addListener(function (data) {
if (data.frameId !== 0) {
// Don't trigger on iframes
return;
}
var tabIdToUrl = {};
tabIdToUrl[data.tabId.toString()] = data.url;
chrome.storage.local.set(tabIdToUrl);
});
And retrieval:
chrome.storage.local.get(tabId, function (item) {
var url = item[tabId];
...
});
I am running into the same issue, really wished that chrome api could return both the before and after url at chrome.tabs.onUpdated event.
My solution is similar to #Oak, but instead of using chrome.storage.local I am using Window.sessionStorage due to the following two reasons:
chrome.storage.local behaves similarly to Window.localStorage, it persists even when the browser is closed and reopened. If you don't do cleanup yourself, your local storage will grow overtime with a lot of redundant information. With session storage, whenever you closed all of your browser instances (end of persistent background page's lifetime). it will conveniently forget everything :)
Window.sessionStorage stores data in strings only, which is good for this use case (tab.url), chrome.storage.local is a more powerful tool, you can save some space when you want to store objects.
my test case is something like this:
chrome.tabs.onUpdated.addListener(function(tabId,changeInfo,tab){
var newUrl = changeInfo.url;
if(newUrl){
window.sessionStorage[tabId] = newUrl;
}
});
Another approach uses the referrer of the page. This requires that:
there must be some way to retrieve the page referrer, either by loading a content script into the page that communicates the referrer to the extension, or by somehow inspecting the web navigation or request as it is happening in the background script to retrieve the Referer header (notice the typo)
the page that referred to the current page must have a referrer policy that provides sufficient information
content-script.js
// notify extension that a page has loaded its content script, and send referrer
chrome.runtime.sendMessage({ referrer: document.referrer });
background.js
chrome.runtime.onMessage.addListener(function(request, sender, sendResponse) {
console.log(sender.tab.id);
console.log(request.referrer);
});
Alternatively, the extension could query a tab to get its referrer. You must ensure the tab is ready (has a loaded content script):
content-script.js
chrome.runtime.onMessage.addListener(function(request, sender, sendResponse) {
sendResponse({ referrer: document.referrer });
});
background.js
function askTabForReferrer(tabId) {
chrome.tabs.sendMessage(tabId, {}, function(response) {
console.log(response.referrer);
});
}
const exisitingTabWithLoadedContentScriptId = 83;
askTabForReferrer(exisitingTabWithLoadedContentScriptId);
I'm rather new to Javascript and Crossrider. I believe what I'm trying to do is a rather simple thing - maybe I missed something here?
I am writing an extension that automatically logs you into Dropbox and at a later time will log you out. I can log the user into Dropbox automatically, but now my client wants me to automatically log those people out of dropbox by FINDING the open Dropbox windows and logging each one of them out.
He says he's seen it and it's possible.
Basically what I want is some code that allows me to get the active tabs, and set the location.href of those tabs. Or even close them. So far this is what I got:
//background.js:
appAPI.ready(function($) {
// Initiate background timer
backgroundTimer();
// Function to run backround task every minute
function backgroundTimer() {
if (appAPI.db.get('logout') == true)
{
// retrieves the array of tabs
appAPI.tabs.getAllTabs(function(allTabInfo)
{
// loop through tabs
for (var i=0; i<allTabInfo.length; i++)
{
//is this dropbox?
if (allTabInfo[i].tabUrl.indexOf('www.dropbox.com')!=-1)
{
appAPI.tabs.setActive(allTabInfo[i].tabId);
//gives me something like chrome-extension://...
window.alert(window.location.href);
//code below doesn't work
//window.location.href = 'https://www.dropbox.com/logout';
}
}
appAPI.db.set('logout',false);
});
window.alert('logged out.');
}
setTimeout(function() {
backgroundTimer();
}, 10 * 1000);
}
});
When I do appAPI.tabs.setActive(allTabInfo[i].tabId); and then window.alert(window.location.href); I get as address "chrome-extension://xxx" - which I believe is the address of my extension, which is totally not what I need, but rather the URL of the active window! More than that, I need to navigate the current window to the log out page... or at least refresh it. Can anybody help, please?
-Rowan R. J.
P.S.
Earlier I tried saving the window reference of the dropbox URL I opened, but I couldn't save the window reference into the appAPI.db, so I changed technique. Help!
In general, your use of the Crossrider APIs looks good.
The issue here is that you are trying to use window.location.href to get the address of the active tab. However, in the background scope, the window object relates to the background page/tab and and not the active tab; hence you receive the URL of the background page. [Note: Scopes can't directly interactive with each others objects]
Since your objective is to change/close the URL of the active dropbox tab, you can achieve this using messaging between scopes. So, in your example you can send a message from the background scope to the extension page scope with the request to logout. For example (and I've taken the liberty to simplify the code):
background.js:
appAPI.ready(function($) {
appAPI.setInterval(function() {
if (appAPI.db.get('logout')) {
appAPI.tabs.getAllTabs(function(allTabInfo) {
for (var i=0; i<allTabInfo.length; i++) {
if (allTabInfo[i].tabUrl.indexOf('www.dropbox.com')!=-1) {
// Send a message to all tabs using tabId as an identifier
appAPI.message.toAllTabs({
action: 'logout',
tabId: allTabInfo[i].tabId
});
}
}
appAPI.db.set('logout',false);
});
}
}, 10 * 1000);
});
extension.js:
appAPI.ready(function($) {
// Listen for messsages
appAPI.message.addListener(function(msg) {
// Logout if the tab ids match
if (msg.action === 'logout' && msg.tabId === appAPI.getTabId()) {
// change URL or close code
}
});
});
Disclaimer: I am a Crossrider employee
My Case: localStorage with key + value that should be deleted when browser is closed and not single tab.
Please see my code if its proper and what can be improved:
//create localStorage key + value if not exist
if (localStorage) {
localStorage.myPageDataArr = {
"name" => "Dan",
"lastname" => "Bonny"
};
}
//when browser closed - psedocode
$(window).unload(function() {
localStorage.myPageDataArr = undefined;
});
should be done like that and not with delete operator:
localStorage.removeItem(key);
Use with window global keyword:-
window.localStorage.removeItem('keyName');
You should use the sessionStorage instead if you want the key to be deleted when the browser close.
You can make use of the beforeunload event in JavaScript.
Using vanilla JavaScript you could do something like:
window.onbeforeunload = function() {
localStorage.removeItem(key);
return '';
};
That will delete the key before the browser window/tab is closed and prompts you to confirm the close window/tab action. I hope that solves your problem.
NOTE: The onbeforeunload method should return a string.
localStorage.removeItem(key); //item
localStorage.clear(); //all items
There is a very specific use case in which any suggestion to use sessionStorage instead of localStorage does not really help.
The use-case would be something as simple as having something stored while you have at least one tab opened, but invalidate it if you close the last tab remaining.
If you need your values to be saved cross-tab and window, sessionStorage does not help you unless you complicate your life with listeners, like I have tried.
In the meantime localStorage would be perfect for this, but it does the job 'too well', since your data will be waiting there even after a restart of the browser.
I ended up using a custom code and logic that takes advantage of both.
I'd rather explain then give code. First store what you need to in localStorage, then also in localStorage create a counter that will contain the number of tabs that you have opened.
This will be increased every time the page loads and decreased every time the page unloads. You can have your pick here of the events to use, I'd suggest 'load' and 'unload'.
At the time you unload, you need to do the cleanup tasks that you'd like to when the counter reaches 0, meaning you're closing the last tab.
Here comes the tricky part: I haven't found a reliable and generic way to tell the difference between a page reload or navigation inside the page and the closing of the tab.
So If the data you store is not something that you can rebuild on load after checking that this is your first tab, then you cannot remove it at every refresh.
Instead you need to store a flag in sessionStorage at every load before increasing the tab counter.
Before storing this value, you can make a check to see if it already has a value and if it doesn't,
this means you're loading into this session for the first time, meaning that you can do the cleanup at load if this value is not set and the counter is 0.
use sessionStorage
The sessionStorage object is equal to the localStorage object, except that it stores the data for only one session. The data is deleted when the user closes the browser window.
The following example counts the number of times a user has clicked a button, in the current session:
Example
if (sessionStorage.clickcount) {
sessionStorage.clickcount = Number(sessionStorage.clickcount) + 1;
} else {
sessionStorage.clickcount = 1;
}
document.getElementById("result").innerHTML = "You have clicked the button " +
sessionStorage.clickcount + " time(s) in this session.";
Try using
$(window).unload(function(){
localStorage.clear();
});
Hope this works for you
There are five methods to choose from:
setItem(): Add key and value to localStorage
getItem(): Retrieve a value by the key from localStorage
removeItem(): Remove an item by key from localStorage
clear(): Clear all localStorage
key(): Passed a number to retrieve nth key of a localStorage
You can use clear(), this method when invoked clears the entire storage of all records for that domain. It does not receive any parameters.
window.localStorage.clear();
for (let i = 0; i < localStorage.length; i++) {
if (localStorage.key(i).indexOf('the-name-to-delete') > -1) {
arr.push(localStorage.key(i));
}
}
for (let i = 0; i < arr.length; i++) {
localStorage.removeItem(arr[i]);
}
8.5 years in and the original question was never actually answered.
when browser is closed and not single tab.
This basic code snippet will give you the best of both worlds. Storage that persists only as long as the browser session (like sessionStorage), but is also shareable between tabs (localStorage).
It does this purely through localStorage.
function cleanup(){
// place whatever cleanup logic you want here, for example:
// window.localStorage.removeItem('my-item')
}
function tabOpened(){
const tabs = JSON.parse(window.localStorage.getItem('tabs'))
if (tabs === null) {
window.localStorage.setItem('tabs', 1)
} else {
window.localStorage.setItem('tabs', ++tabs)
}
}
function tabClosed(){
const tabs = JSON.parse(window.localStorage.getItem('tabs'))
if (tabs === 1) {
// last tab closed, perform cleanup.
window.localStorage.removeItem('tabs')
cleanup()
} else {
window.localStorage.setItem('tabs', --tabs)
}
}
window.onload = function () {
tabOpened();
}
window.onbeforeunload = function () {
tabClosed();
}
why not used sessionStorage?
"The sessionStorage object is equal to the localStorage object, except that it stores the data for only one session. The data is deleted when the user closes the browser window."
http://www.w3schools.com/html/html5_webstorage.asp
Although, some users already answered this question already, I am giving an example of application settings to solve this problem.
I had the same issue. I am using https://github.com/grevory/angular-local-storage module in my angularjs application. If you configure your app as follows, it will save variable in session storage instead of local storage. Therefore, if you close the browser or close the tab, session storage will be removed automatically. You do not need to do anything.
app.config(function (localStorageServiceProvider) {
localStorageServiceProvider
.setPrefix('myApp')
.setStorageType('sessionStorage')
});
Hope it will help.
Here's a simple test to see if you have browser support when working with local storage:
if(typeof(Storage)!=="undefined") {
console.log("localStorage and sessionStorage support!");
console.log("About to save:");
console.log(localStorage);
localStorage["somekey"] = 'hello';
console.log("Key saved:");
console.log(localStorage);
localStorage.removeItem("somekey"); //<--- key deleted here
console.log("key deleted:");
console.log(localStorage);
console.log("DONE ===");
} else {
console.log("Sorry! No web storage support..");
}
It worked for me as expected (I use Google Chrome).
Adapted from: http://www.w3schools.com/html/html5_webstorage.asp.
I don't think the solution presented here is 100% correct because window.onbeforeunload event is called not only when browser/Tab is closed(WHICH IS REQUIRED), but also on all other several events. (WHICH MIGHT NOT BE REQUIRED)
See this link for more information on list of events that can fire window.onbeforeunload:-
http://msdn.microsoft.com/en-us/library/ms536907(VS.85).aspx
After looking at this question 6 years after it was asked, I found that there still is no sufficient answer to this question; which should achieve all of the following:
Clear Local Storage after closing the browser (or all tabs of the domain)
Preserve Local Storage across tabs, if at least one tab remains active
Preserve Local Storage when reloading a single tab
Execute this piece of javascript at the start of each page load in order to achieve the above:
((nm,tm) => {
const
l = localStorage,
s = sessionStorage,
tabid = s.getItem(tm) || (newid => s.setItem(tm, newid) || newid)((Math.random() * 1e8).toFixed()),
update = set => {
let cur = JSON.parse(l.getItem(nm) || '{}');
if (set && typeof cur[tabid] == 'undefined' && !Object.values(cur).reduce((a, b) => a + b, 0)) {
l.clear();
cur = {};
}
cur[tabid] = set;
l.setItem(nm, JSON.stringify(cur));
};
update(1);
window.onbeforeunload = () => update(0);
})('tabs','tabid');
Edit: The basic idea here is the following:
When starting from scratch, the session storage is assigned a random id in a key called tabid
The local storage is then set with a key called tabs containing a object those key tabid is set to 1.
When the tab is unloaded, the local storage's tabs is updated to an object containing tabid set to 0.
If the tab is reloaded, it's first unloaded, and resumed. Since the session storage's key tabid exists, and so does the local storage tabs key with a sub-key of tabid the local storage is not cleared.
When the browser is unloaded, all session storage will be cleared. When resuming the session storage tabid won't exists anymore and a new tabid will be generated. Since the local storage does not have a sub-key for this tabid, nor any other tabid (all session were closed), it's cleared.
Upon a new created tab, a new tabid is generated in session storage, but since at least one tabs[tabid] exists, the local storage is not cleared
This will do the trick for objects.
localStorage.removeItem('key');
Or
localStorage.setItem('key', 0 );
You can simply use sessionStorage. Because sessionStorage allow to clear all key value when browser window will be closed .
See there : SessionStorage- MDN
This is an old question, but it seems none of the answer above are perfect.
In the case you want to store authentication or any sensitive information that are destructed only when the browser is closed, you can rely on sessionStorage and localStorage for cross-tab message passing.
Basically, the idea is:
You bootstrap from no previous tab opened, thus both your localStorage and sessionStorage are empty (if not, you can clear the localStorage). You'll have to register a message event listener on the localStorage.
The user authenticate/create a sensitive info on this tab (or any other tab opened on your domain).
You update the sessionStorage to store the sensitive information, and use the localStorage to store this information, then delete it (you don't care about timing here, since the event was queued when the data changed). Any other tab opened at that time will be called back on the message event, and will update their sessionStorage with the sensitive information.
If the user open a new tab on your domain, its sessionStorage will be empty. The code will have to set a key in the localStorage (for exemple: req). Any(all) other tab will be called back in the message event, see that key, and can answer with the sensitive information from their sessionStorage (like in 3), if they have such.
Please notice that this scheme does not depend on window.onbeforeunload event which is fragile (since the browser can be closed/crashed without these events being fired). Also, the time the sensitive information is stored on the localStorage is very small (since you rely on transcients change detection for cross tab message event) so it's unlikely that such sensitive information leaks on the user's hard drive.
Here's a demo of this concept: http://jsfiddle.net/oypdwxz7/2/
There are no such the way to detect browser close so probably you can't delete localStorage on browser close but there are another way to handle the things you can uses sessionCookies as it will destroy after browser close.This is I implemented in my project.
if(localStorage.getItem("visit") === null) {
localStorage.setItem('visit', window.location.hostname);
console.log(localStorage.getItem('visit'));
}
else if(localStorage.getItem('visit') == 'localhost'){
console.log(localStorage.getItem('visit'));
}
else {
console.log(localStorage.getItem('visit'));
}
$(document).ready(function(){
$("#clickme").click(function(){
localStorage.setItem('visit', '0');
});
});
window.localStorage.removeItem('visit');
window.addEventListener('beforeunload', (event) => {
localStorage.setItem("new_qus_id", $('.responseId').attr('id'));
var new_qus_no = localStorage.getItem('new_qus_id');
console.log(new_qus_no);
});
if (localStorage.getItem('new_qus_id') != '') {
var question_id = localStorage.getItem('new_qus_id');
} else {
var question_id = "<?php echo $question_id ; ?>";
}
you can try following code to delete local storage:
delete localStorage.myPageDataArr;