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

See also

• JavaScript typed arrays
• TypedArray
• TypedArray.prototype.entries()
• TypedArray.prototype.values()
• TypedArray.prototype[@@iterator]()
• for...of
• Iteration protocols