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Understanding Web Storage: LocalStorage, SessionStorage, and Cookies

Abhay Kumar on August 30, 2024

In modern web development, managing data on the client side has become an essential skill. Developers often rely on localStorage, sessionStorage, a...
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GreenerSoft

One interesting thing to note with localStorage or sessionStorage is the “storage” event.

With this event, a browser tab (or window) can synchronize if the localStorage or sessionStorage is updated in another browser tab (or window).

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Faizan

Does this thing utilize "storage" event for the window animation syncing?
youtu.be/aKPkYY-CYuw

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GreenerSoft

Yes, I think so, if you look at this project file.

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José Pablo Ramírez Vargas

The storage event only happens for local storage. This event is in direct contradiction to the definition of session storage.

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GreenerSoft

Yes, it is not possible to synchronize a tab or window with the storage event for sessionStorage, since sessionStorage is private to each tab or window.

However, the storage event is sent in certain cases for sessionStorage, for example if you modify sessionStorage using the browser's developer tools.

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Anmol Baranwal

Nice read 👏

There is no usage of tags at the end.. just letting you know.
You might not know but there is a hooks system to use localstorage: mantine.dev/hooks/use-local-storage/

Not preferable to install a package but I thought it would be worth sharing here if anybody wants to check it out.

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Abhay Kumar

I know about that, but you have to install the Mantine UI library. then only you can use this hook. thanks for your feedback.

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Andrea Giammarchi

cookies need decodeURIComponent for likely both the key and their values ... please update the example code accordingly, or surprises will happen 👋

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Aakash

The best explaination between the localStorage, sessionStorage and cookies..

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Md Nazmus Sakib

very Impressive

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ChesedGamesOnline

Very well written! Even I could understand

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cuongnp

I love this one! Recently, I faced a couple of issues with them. Thanks for sharing!

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jacquelinehartnick06@gmail.com

I'm out of storage for almost one year and struggling alot even with phone storage

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Ahtesham Abdul Aziz

Thanks for the explanation mate.

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the-pro7

Thanks for the information ☺️

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João Victor

Nicely explained

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ZeeshanAli-0704

Thanks

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Marcin

If writing about data storage for web why didn't you include serviceWorkers' cache and indexDB?

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Muhammad Shahidul Islam

Thanks for the nice explanation.

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Yusra Saeed

Nicely explained

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Andrew Baisden

That's a great explanation; by the way, you can add syntax highlighting to the code blocks to boost readabilty.

Just change:

code block with no colors example

... to specify the language:

code block with colors example

More details can be found here --> editor guide!

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Ilya Belous • Edited

LocalStorage is used for persistent client-side storage, surviving across sessions, while sessionStorage is temporary and only lasts for a session. Cookies store small data sent with HTTP requests, with configurable expiration. The post above provides examples and guidance on when to use each, such as storing user preferences or authentication tokens... Just summarized all of that for ya 😈

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abdulghani ibrahim

Thank you in information technology

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Omura

thanks for your effort. It's amazing.
In the past I used localstorage, but after reading this article, I recognized my fault.
I'm waiting for your next articles.

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Yogesh Joshi

nice

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legrandmawak

It might be a good idea to point out that both localStorage are limited to a single host (URL). Therefore if you want/need to share information to multiple URL, port, domain. You must use cookie.

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mhdajmal-k

Thank you for sharing the valuable information

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RogeClash

amazing , thank you

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Tomas Stveracek

Great summary of web storage options! This will be really helpful for beginners. Maybe also consider adding a note about IndexedDB for more advanced storage needs. Thanks for sharing! 👏

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KC

What about redis? @abhay1kumar