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typedArray.keys

The keys() method returns a new Array Iterator object that contains the keys for each index in the array.

Syntax

arr.keys()

Return value

A new Array Iterator object.

Examples

Iteration using for...of loop

var arr = new Uint8Array([10, 20, 30, 40, 50]);
var eArray = arr.keys();
// your browser must support for..of loop
// and let-scoped variables in for loops
for (let n of eArray) {
  console.log(n);
}

Alternative iteration

var arr = new Uint8Array([10, 20, 30, 40, 50]);
var eArr = arr.keys();
console.log(eArr.next().value); // 0
console.log(eArr.next().value); // 1
console.log(eArr.next().value); // 2
console.log(eArr.next().value); // 3
console.log(eArr.next().value); // 4

Specifications

Specification Status Comment
ECMAScript 2015 (6th Edition, ECMA-262)
The definition of '%TypedArray%.prototype.keys()' in that specification.
Standard Initial definition.
ECMAScript 2017 Draft (ECMA-262)
The definition of '%TypedArray%.prototype.keys()' in that specification.
Draft

Browser compatibility

Feature Chrome Edge Firefox (Gecko) Internet Explorer Opera Safari
Basic support (Yes) (Yes) 37 (37) No support No support 10
Feature Android Chrome for Android Firefox Mobile (Gecko) IE Mobile Opera Mobile Safari Mobile
Basic support No support (Yes) 37.0 (37) No support No support 10

See also

© 2005–2017 Mozilla Developer Network and individual contributors.
Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray/keys