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This feature is well established and works across many devices and browser versions. Its been available across browsers since julho de 2015.
O mtodo keys() retorna um novo Array Iterator que contm as chaves para cada index do array.
arr.keys()
var arr = ["a", "b", "c"];
var iterator = arr.keys();
console.log(iterator.next()); // { value: 0, done: false }
console.log(iterator.next()); // { value: 1, done: false }
console.log(iterator.next()); // { value: 2, done: false }
console.log(iterator.next()); // { value: undefined, done: true }
var arr = ["a", , "c"];
var sparseKeys = Object.keys(arr);
var denseKeys = [...arr.keys()];
console.log(sparseKeys); // [0, 2]
console.log(denseKeys); // [0, 1, 2]
| Specification |
|---|
| ECMAScript 2027 LanguageSpecification # sec-array.prototype.keys |
This page was last modified on 3 de fev. de 2024 by MDN contributors.
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