How to retrieve all localStorage items without knowing the keys in advance?

Question

I want to show all of the keys and storage written before. My code is below. I created a function (allStorage) but it doesn\'t work. How can I do this?

Answer 1

The easiest way in ES2015+ is:

const items = { ...localStorage };

Answer 2

// iterate localStorage
for (var i = 0; i < localStorage.length; i++) {

  // set iteration key name
  var key = localStorage.key(i);

  // use key name to retrieve the corresponding value
  var value = localStorage.getItem(key);

  // console.log the iteration key and value
  console.log('Key: ' + key + ', Value: ' + value);  

}

Answer 3

for (let [key, value] of Object.entries(localStorage)) {
    console.log(`${key}: ${value}`);
}

Answer 4

If you modify your function to this you can list all items based on key (will list the items only):

function allStorage() {

    var values = [],
        keys = Object.keys(localStorage),
        i = keys.length;

    while ( i-- ) {
        values.push( localStorage.getItem(keys[i]) );
    }

    return values;
}

Object.keys is a new addition to JavaScript (ECMAScript 5). It lists all own keys on an object which is faster than using a for-in loop which is the option to this.

However, this will not show the keys. For that you need to return an object instead of an array (which is rather point-less IMO as this will bring you just as far as you were before with localStorage just with a different object - but for example's sake):

function allStorage() {

    var archive = {}, // Notice change here
        keys = Object.keys(localStorage),
        i = keys.length;

    while ( i-- ) {
        archive[ keys[i] ] = localStorage.getItem( keys[i] );
    }

    return archive;
}

If you want a compact format listing then do this instead - here each item in the array will have key=item which you later can split into pairs and so forth:

function allStorage() {

    var archive = [],
        keys = Object.keys(localStorage),
        i = 0, key;

    for (; key = keys[i]; i++) {
        archive.push( key + '=' + localStorage.getItem(key));
    }

    return archive;
}

Answer 5

localStorage is not an array, but an object, so try sth. like this:

for (var a in localStorage) {
   console.log(a, ' = ', localStorage[a]);
}

Answer 6

A little more succinct:

function getAllLocalStorage() {
    return Object.keys(localStorage)
        .reduce((obj, k) => {
            return { ...obj, [k]: localStorage.getItem(k)}}, {});
        }