Append objects in local storage

Question

I store objects in local storage with the following:

 localStorage.setItem('obj', JSON.stringify(obj));

I want to add multiple instances of obj every one second, giving a time key. How can I append obj instead of change it every time?

Answer 1

var oldItems = JSON.parse(localStorage.getItem('itemsArray')) || [];

var newItem = 
{
 'product-name': itemContainer.find('h2.product-name a').text(),
 'product-image': itemContainer.find('div.product-image img').attr('src'),
 'product-price': itemContainer.find('span.product-price').text()
};

 oldItems.push(newItem);

 localStorage.setItem('itemsArray', JSON.stringify(oldItems));

You may also want to consider using an object instead of an array and use the product name as the key. This will prevent duplicate entries showing up in LocalStorage.

Answer 2

Basically you have to retrieve the object, add your value and then write it back to localStorage.

var obj = JSON.parse( localStorage.getItem('obj') ) || {};
obj[ timestamp ] = 'newvalue';
localStorage.setItem('obj', JSON.stringify(obj));