The keys()
method returns a new Array Iterator
object that contains the keys for each index in the array.
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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 |
---|
ECMAScript (ECMA-262) The definition of '%TypedArray%.prototype.keys()' in that specification. |
Browser compatibility
The compatibility table on this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request.
Desktop | Mobile | Server | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|
keys | Chrome Full support 38 | Edge Full support 14 | Firefox Full support 37 | IE No support No | Opera Full support 25 | Safari Full support 10 | WebView Android Full support 38 | Chrome Android Full support 38 | Firefox Android Full support 37 | Opera Android Full support 25 | Safari iOS Full support 10 | Samsung Internet Android Full support 3.0 | nodejs Full support 0.12 |
Legend
- Full support
- Full support
- No support
- No support