No, there is no such built-in functionality. See the spec for the Storage interface: interface Storage { readonly attribute unsigned long length; DOMString? key(unsigned long index); getter DOMString getItem(DOMString key); setter creator void setItem(DOMString key, DOMString value); deleter void removeItem(DOMString key); void clear(); }; And the following line just to confirm that further: The getItem(key) … Read more
The current answers are overlooking a really simple and secure option: window.dispatchEvent. Where you set your localStorage item, if you dispatch an event at the same time then the eventListener in the same browser tab (no need to open another or mess with state) will also pick it up: const handleLocalStorage = () => { … Read more
Yes, it is thread safe. However, your code isn’t atomic and that’s your problem there. I’ll get to thread safety of localStorage but first, how to fix your problem. Both tabs can pass the if check together and write to the item overwriting each other. The correct way to handle this problem is using StorageEvents. … Read more
Functions in javascript are more than just their code. They also have scope. Code can be stringified, but scope cannot. JSON.stringify() will encode values that JSON supports. Objects with values that can be objects, arrays, strings, numbers and booleans. Anything else will be ignored or throw errors. Functions are not a supported entity in JSON. … Read more
Store the value you’d like to keep in another variable, then use localStorage.clear() Example: var myItem = localStorage.getItem(‘key’); localStorage.clear(); localStorage.setItem(‘key’,myItem); Example was taken from this SO post.
This question was on my head when I started developing react apps. There are many reasons than below to use redux over localStorage. but at least Using Redux alongside react-redux is not only for store data. don’t forget that changing in a state will reRender All components that listen to that state. and that is … Read more
Are you testing this on a local HTML file? i.e. a file:/// URL? localStorage is only available on HTTP websites. That hasn’t changed in IE9 Dev Preview.
There are a few steps you need to take to properly store this information in your localStorage. Before we get down to the code however, please note that localStorage (at the current time) cannot hold any data type except for strings. You will need to serialize the array for storage and then parse it back … Read more
Well, rather than looking at the vulnerability, let’s look at the possible attack vectors. I’ll add a table here as a TL/DR Attacker | Vulnerable? Eavesdropper | Yes MITM | Yes Local Attack | Yes Server Attack | Yes So yes, it is an issue. Remote Attacker, can observe traffic, but cannot modify traffic Consider … Read more