javascript - how to clone Array without reference

Question

I'm trying to clone Array to a new one, and I want cloned array has no reference to original copy

I know there're splice and from method, but new array from those methods all has reference to original array

e.g.

let original = [ [1,2], [3,4] ];
let cloned = Array.from(original); // this will copy everything from original 
original[0][0] = -1;
console.log(cloned[0][0]); // the cloned array element value changes too

I also tried using loop to have cloned[i][j] = original[i][j], but result is the same

How can I create a new Array with every element having same value from original Array, but the cloned Array should have no reference to original Array?

thanks!

`Array.prototype.slice` copies the array – Ilia Choly Jan 12 '18 at 04:21 — Ilia Choly, Jan 12 '18 at 04:21

score 20 · Accepted Answer · answered Jan 12 '18 at 04:23

20

By using this method we can create a copy of an array. Please check the below example. Credits to this SO Answer

let original = [
  [1, 2],
  [3, 4]
];
let cloned = JSON.parse(JSON.stringify(original)); // this will copy everything from original 
original[0][0] = -1;
console.log(cloned); // the cloned array element value changes too
console.log(original);

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answered Jan 12 '18 at 04:23

Naren Murali

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awesome! this is exactly what I need! – jerry Jan 12 '18 at 05:44
@jerry You're welcome! – Naren Murali Jan 12 '18 at 05:46
This works smoothly! – Rddevelop Feb 28 '19 at 09:57
this solution worked like a charm, tried to slice method and did not make it work. Thank u. – Coder0997 Jun 10 '20 at 16:34

javascript - how to clone Array without reference

1 Answers1