How to delete a specific item/object in localStorage?

All the answers were right but you have to :

1. Parse the string in localStorage to JSON (you did that)
2. Remove the item you don't want (with slice() )
3. Make the JSON to string
4. Re-set it in the localStorage

So :

1.

var items = JSON.parse(localStorage.getItem("items")); // updated

2.

for (var i =0; i< items.length; i++) {
    var items = JSON.parse(items[i]);
    if (items.itemId == 3) {
        items.splice(i, 1);
    }
}

3.

items = JSON.stringify(items); //Restoring object left into items again

4.

localStorage.setItem("items", items);

Parsing to JSON and storing it as string is kinda annoying, but that's the way localStorage works.

Try this one.

$("#button_delete").on("click", function(e){
  e.preventDefault();

  var items = JSON.parse(localStorage["items"]);
  for (var i = 0; i < items.length; i++) {
     if(items[i].itemId == 3){
       items.splice(i,1);
       break;
     }
  }
})

If you know the key of the specific item - do it short and simple like this:

if (localStorage.getItem('key_to_remove') != null)
            localStorage.removeItem('key_to_remove');