a month ago

How can a function that utilizes session storage be triggered upon retrieval of session storage?

The question is currently closed because it requires debugging details and is not accepting any answers. However, the OP wants to run a function not with the onClick event, but when something is stored in the Session Storage. They tried using an eventListener, but it didn't work. The provided code retrieves an array of selected nodes from sessionStorage and adds each one to a chart if it exists. If there are no selected nodes, the function returns early. Finally, the selected nodes are removed from sessionStorage.
a month ago
Verified Answer
You can use the window.onstorage event to listen for changes in the session storage. Here is an example of how to use it:
window.onstorage = function(e) {
  if (e.storageArea === sessionStorage) {
    if (sessionStorage.getItem('yourKey') !== null) {
      // your function here
This code will run your function when something is stored in the session storage. You can replace yourKey with the key you want to listen for changes on. I hope this helps! Let me know if you have any other questions.


How do I run a function once session storage is != undefinedHow and When to Apply Session Storage with JavaScriptStorage - Web APIs | MDN - Mozilla DeveloperHow can a function that uses session storage be executed when session ...How to set/get/save data in session storage? - Stack Overflow
a month ago
To run the mobileHandler function when something is stored in the Session Storage instead of using the onClick event, you can listen to the storage event on the window object. Here's an example of how you can modify the code:
function mobileHandler(event) {

  // Get the selectedNodes array from sessionStorage
  const selectedNodes = JSON.parse(sessionStorage.getItem('selectedNodes'));

  // If no selectedNodes, return early
  if (!selectedNodes) return;

  // Loop through each selected node and add it to the chart
  selectedNodes.forEach((nodeData) => {
    console.log('Adding node:', nodeData);

  // Clear the selectedNodes from sessionStorage

// Listen to the storage event on the window object
window.addEventListener('storage', (event) => {
  if (event.key === 'selectedNodes') {
In this modified code, we have added an event listener that listens to the storage event on the window object. When the selectedNodes key is set in the Session Storage, the mobileHandler function is called and the nodes are added to the chart.