I am storing some data in the local storage using
localstorage.setItem("key","value")
I understand that localstorage is browser specific, now will this value remain even after i login as different user (sharepoint) in the same browser?
as far as i know localStorage is persistent until user clears it
and i read in this SO question that
Duration
In DOM Storage it is not possible to specify an expiration period for
any of your data. All expiration rules are left up to the user. In the
case of Mozilla, most of those rules are inherited from the
Cookie-related expiration rules. Because of this you can probably
expect most of your DOM Storage data to last at least for a meaningful
amount of time.
So does this mean that local storage is only browser specific? ie even if login as different user in sharepoint, the localstorage values will still remain if i use the same browser? (given that i dont clear it in log out/log in actions in sharepoint)
I understand that localstorage is browser specific, now will this value remain even after i login as different user in the same browser?
Yes.
Definitely.
It has nothing to do with php sessions or the like. Nothing.
LocalStorage is attached to the browser. Log in or log out, has no effect on localStorage.
even if login as different user, the localstorage values will still remain if i use the same browser?
Yes.
You can wrap browser storage with your own interface. It can have expiration by setting a timestamp on writes and checking it on reads.
var Storage = {
get: function (key) {
var item = localStorage.getItem(key)
if (item) {
var entry = JSON.parse(item)
if (entry.expires && Date.now() > entry.expires) {
localStorage.removeItem(key)
} else {
return entry.data
}
}
},
set: function (key, value, expires) {
var entry = { data: value }
if (expires) { entry.expires = expires }
var item = JSON.stringify(entry)
localStorage.setItem(key, item)
},
}
Related
I have below scenario
Page 1 has a link, when user clicks on it, it gets navigated to portal page with page reload. So just before navigation, a JSON object is created
The size of this object comes around 4KB roughly.
Sample object
let obj = {
"date":"12/31/2018",
"year":"2019",
"zip":"93252",
"members":[
{
"sdf":true,
"age":21,
"fdssss":false,
"aaaa":false,
"fdss":null,
"fsdfsd":[
"ADULT"
]
},
{
"sdf":true,
"age":21,
"fdssss":false,
"aaaa":false,
"fdss":null,
"fsdfsd":[
"ADULT"
]
}
}
There is a back link from that portal page, on clicking page will be navigated back to Page 1 with a page reload.
So when the page is navigated back, I need the created JSON object back again. I need it only for that session or the data should be persistent even if the page is reloaded.
Do I have to use localStorage? If i store the object in localStorage, at what point i should clear the storage? How should I handle between different users?
Do I have to use sessionStorage? what will be the scope of the data availability
I'm using AWS service.
Q1:
you can have localStorage, and you should handle it at the code when first page loaded and you can delete it when user do signout or login, storage is about browser not user, if there are some users behind one computer at different times you must clear all data manually.
Q2:
you can also have sessionStorage, per tab and will be removed by closing browser.
in details:
This is depends on your scenario which means localStorage used for long time but sessionStorage used when you need to store something temporary.
but the important thing about sessionStorage is that it is exist per tab if you close tab and windows the sessionStorage completely removed, it used for critical data such as username and password whereas localStorage is used to shared data whole the browser.
localStorage has no expiration date, and it gets cleared only by code, or clearing the browser cache or locally stored data whereas sessionStorage object stores data only for a session, meaning that the data is stored until the browser (or tab) is closed.
at the end I suggest you to use localStorage because you may want to share that data whole the browser event after closing browser and you can store more data, in the other side there are limitation about them, when you are used storage you should handle them manually and take care.
suppose:
function removeStorage()
{
var obj = localStorage.getItem('obj');
if(obj !== null)
localStorage.removeItem('obj')
}
and in login or logout success action call removeStorage() and in Page1 load have something like below:
var obj = localStorage.getItem('obj');
if(obj !== null)
{
....
//show the obj in label or do what you want with it
...
}
I'm currently testing on my local machine so the URL is as following when the user presses Sign out
// The ********** is my site name, which i don't want releasing yet
http://localhost:8080/**********/logout/
Local storage item:
Key: tkn Value: EE8D9DA0F1D71A0BE8B80F3BA80343555655871151tk16
the following tests i've tried:
if (localStorage.getItem('tkn')) {
localStorage.clear();
}
if (localStorage.getItem('tkn')) {
localStorage.removeItem('tkn');
}
// I've also ran these both tests in the console of the browser
// and they return back 'undefined' but the item is cleared.
However when I sign out, the user session is removed completely fine. However the localStorage doesn't seem to be cleared.
Could someone shred some light on this for me?
Instead of checking a specific property, check the length
if (localStorage.length > 0 ) {
localStorage.clear();
}
localStorage is an implementation of Storage interface and Storage has a property called length
Storage.length
Returns an integer representing the number of data items stored in the
Storage object.
I'm a new learner for API, and I have a quesion about local storage. This is a code example from my javascript book:
if (Modernizr.localstorage) {
var txtUsername = document.getElementById('username');
var txtAnswer = document.getElementById('answer');
txtUsername.value = localStorage.getItem('username');
txtAnswer.value = localStorage.getItem('answer');
txtUsername.addEventListener('input', function () {
localStorage.setItem('username', txtUsername.value);
}, false);
txtAnswer.addEventListener('input', function () {
localStorage.setItem('answer', txtAnswer.value); }, false);
}
}
I want to ask why should we "localStorage.getItem()" part? Cause I think if user type their username, then we can get their names just from the variable "txtUsername" cause I thought it should be setItem first and then getItem. Thank you!
Local storage is used to store small amounts of data on the client side. What does your code ?!
For example: A user visited the site for the first time and complete the inputs, , the data stored in the local store. The user closed the browser. The next day he again went to the site to fill out the form again, and its data is already filled. Conveniently!
Also we can use local storage as js object
txtUsername.value = localStorage.getItem('username');
txtUsername.value = localStorage.username;
txtUsername.value = localStorage['username'];
The thing is, it works just as you said.
It's just, when person types data in the textbox he uses setItem - that what 'input' eventListener used for
Think of LocalStorage as of really light database that keeps data even when user closes the page
But since it can store data when page is closed, you want to show the content of it in the textbox - and that's why author uses 'getItem' on start
how to localhost saved values check using java script,Button on click based saving one value,after page refresh want to check check value save,How to check
Dear you can use SESSION variable for it. You can store checked checkbox value in an index on array and that array stored in Session Variable. So by this way you will get all checked values and can use anywhere.
What is HTML5 Web Storage?
With HTML5, web pages can store data locally within the user's browser.
Earlier, this was done with cookies. However, Web Storage is more secure and faster. The data is not included with every server request, but used ONLY when asked for. It is also possible to store large amounts of data, without affecting the website's performance.
The data is stored in name/value pairs, and a web page can only access data stored by itself.
Unlike cookies, the storage limit is far larger (at least 5MB) and information is never transferred to the server.
Example:
function getItem(key){
if (!hasLocalStorage || !key) return;
return localStorage.getItem(key);
}
function setItem(key, val){
if (!hasLocalStorage || !key) return;
localStorage.setItem(key, val);
}
function hasLocalStorage () {
return typeof window.localStorage !== 'undefined';
}
//to store an item
setItem("itemKey", "itemVal");
//to retrieve an (the above, in this case) item
var fetchItem = getItem("itemKey");
Did you try to store that value in cookies?
Let's say I have two or more tabs with a couple of inputs and textareas.
Users can fill these fields and switch tabs but I want to make sure they don't lose the data in the fields.
Here comes the question: how would you save the data when the users switch between tabs?
Now I solved this problem by storing the data in variables, specifically in object literal (Javascript), but it is such a mechanical way to do it.
Of course I could push the data in a database.
I am using Javascript plus jQuery. I would really like to think of a good way to solve this kind of problem.
You can use localStorage.
Just set the values you want to store by:
localStorage.setItem(key, stringData);
To get the data:
var stringData = localStorage.getItem(key);
To delete:
localStorage.removeItem(key);
That way the data is stored locally in the user's browser. User can also come back later and data will still be there.
You can synchronize the tabs by listening the storage event:
window.addEventListener('storage', updateStorage, false);
function updateStorage(e) {
if (e.newValue === null) {
localStorage.removeItem(e.key);
} else {
localStorage.setItem(e.key, e.newValue);
}
}
The storageevent is only throw to the inactive tabs so they can update the isolated copy of the localStorage.
If you only need to store the data for a session you can use sessionStorage instead.
For more on localStorage:
http://www.w3.org/TR/2013/PR-webstorage-20130409/