How to convert objects into an array?

Question

I have stored data in local storage in an array. Now I want to remove certain item from that array present in local storage. For that first I have

var items = JSON.parse(localStorage.getItem('shoppingCart'));
var resturantid = localStorage.getItem('resturant_id');
var filtered = [];
for (var q = 0; q < items.length; q++) {

  if (items[q].resturantid == resturantid) {
    filtered.push(items[q]);
  }
}
console.log(typeof filtered, filtered);

output is OBJECT

in console

(2) [{…}, {…}]
0: {name: "veg-momo", price: 12, count: 8, resturant: "Test Developer", resturantid: 2, …}
1: {name: "afdafasdf", price: 123, count: 4, resturant: "Test Developer", resturantid: 2, …}
length: 2
__proto__: Array(0)

typeof gives me object and because of this I haven't been able to use map function as it says array.map is not a function. I want these things to happen just to remove certain item in local storage key in which array is set.

Does this answer your question? [How do I loop through or enumerate a JavaScript object?](https://stackoverflow.com/questions/684672/how-do-i-loop-through-or-enumerate-a-javascript-object) — imvain2, Jul 13 '20 at 17:53
What is `array` and where are you calling `array.map`? That's not in your code. — D. Pardal, Jul 13 '20 at 17:54
`typeof myArray` *always* gives "Object". Don't let that dissuade you from using myArray.map. — James, Jul 13 '20 at 17:55
Use `Array.isArray` if you want to know if a variable is an array. — Heretic Monkey, Jul 13 '20 at 18:36

Arun Saini · Accepted Answer · 2020-07-13T19:18:25.410

Your object is something like {0: {…}, 1: {…}} you need to make an array of values like [{...}, {...}]! To do so use Object.values() and then apply map() or filter() or reduce() as per your program needs.

let obj = Object.assign({},[{name: "veg-momo", price: 12, count: 8, resturant: "Test Developer", resturantid: 2}, {name: "afdafasdf", price: 123, count: 4, resturant: "Test Developer", resturantid: 2}]);

// obj.map(x => {console.log(x)}); //error: Uncaught TypeError: obj.map is not a function

Object.values(obj).map(x => console.log(x)); // Works!

score -1 · Answer 2 · edited Jul 13 '20 at 18:35

-1

The problem is that you have to use filtered[0].name etc Because in HTML there is no object so you have to use this

But if you want to display in HTML you can use filtered[0].toString() And print it

edited Jul 13 '20 at 18:35

Heretic Monkey

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answered Jul 13 '20 at 18:02

Lonely

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Please read [answer] for information on how to answer. Feel free to browse the other articles in the [help] to familiarize yourself with the site and how it works before using it. – Heretic Monkey Jul 13 '20 at 18:35

score -1 · Answer 3 · answered Jul 13 '20 at 18:35

-1

This isn't an appropriate use of map(); this returns a new array with elements for all the original elements. Use filter() to return only the elements that satisfy a test.

var filtered = items.filter(item => item.restaurantid == restaurantid);

Your object is an array, so all the standard array methods should work for it.

answered Jul 13 '20 at 18:35

Barmar

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Issues is with an object which is something like {0: {…}, 1: {…}}, not an array. – Arun Saini Jul 13 '20 at 19:20
Where did you get that from? The question starts with "I have stored data in local storage in an array." – Barmar Jul 13 '20 at 19:23
localStorage does not support the array – Arun Saini Jul 13 '20 at 19:26
@ArunSaini The array is converted to JSON, and JSON supports both arrays and objects. – Barmar Jul 13 '20 at 19:28

How to convert objects into an array?

3 Answers3