Widely availableSupported across all major browsers. Safe to use in production.
Arrays Widely available

Array copyWithin()

The copyWithin() method of arrays and typed arrays shifts or copies items of an array to another index of the array without changing its length.

Arrays

Overview

The copyWithin() method of arrays and typed arrays shifts or copies items of an array to another index of the array without changing its length.

Browser support

Feature Desktop Mobile
Chrome
Edge
Firefox
Safari
Chrome Android
Safari iOS
javascript.builtins.Array.copyWithin
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12
32
9
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9
Built-in object
TypedArray.copyWithin

The copyWithin() method of TypedArray instances shallow copies part of this typed array to another location in the same typed array and returns this typed array without modifying its length. This method has the same algorithm as Array.prototype.copyWithin().
45
12
34
10
45
10
1+Supported (version) Not supported ※Has note Sub-feature descriptions sourced from MDN Web Docs (CC BY-SA 2.5)

Syntax

JAVASCRIPT 
const arr = [1, 2, 3, 4, 5];

arr.copyWithin(0, 3); // [4, 5, 3, 4, 5]
arr.copyWithin(1, 3, 4); // [4, 4, 3, 4, 5]

Live demo

Element. shifut

Arrayinside. Element, by. index to topwrite..

PreviewFullscreen

specificrange. topwrite

index1 from 1elementsplitonly, 3th. Element in topwrite..

PreviewFullscreen

repeatpattern. Create

Array. beforepartial after to copi-, repeat make..

PreviewFullscreen

Use cases

  • Using Array copyWithin()

    The copyWithin() method of arrays and typed arrays shifts or copies items of an array to another index of the array without changing its length.

Cautions

  • No specific concerns. Stable across all major browsers.

Accessibility

  • When updating the DOM dynamically, announce important changes to assistive technology with aria-live regions.

Related links

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