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Tolerim
a day ago

How can I identify when the user has cleared cookies?

As a senior JavaScript developer, I have been tasked with detecting when a user clears their cookies or session storage. Is it possible for JavaScript to detect this event? Additionally, I am interested in identifying which user is responsible for clearing the cookies.

Answers(1)
avatar
Tolerim
a day ago
Verified Answer
Yes, you can use JavaScript to detect when a user clears their cookies or session storage by using the StorageEvent object. First, you will need to add an event listener to the window object for the storage event. This event fires whenever a change is made to the localStorage or sessionStorage object. 
window.addEventListener('storage', function(event) {
  // Code to handle storage event
});
Inside the event listener, you can check whether the event was triggered by a clear operation by checking if the newValue property of the StorageEvent object is null. If it is null, it means that the storage area was cleared. 
window.addEventListener('storage', function(event) {
  if (event.newValue === null) {
    // Storage was cleared
    console.log('Storage was cleared by user: ' + event.key);
  }
});
Note that the event.key property will contain the key of the item that was deleted, so you can use this to determine which user cleared their cookies. Also note that the storage event does not fire for changes made within the same page/tab, so if the user clears their cookies in a different tab, the event will fire in all other tabs except the one where the change was made.
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