Array.prototype.values() returns a new Array Iterator that yields each element value from start to end. It does not copy the array or run a callback. On arrays, for...of uses the same idea via Symbol.iterator.
array.values() → iterator of element values
values() → apple, orange, banana
keys() → 0, 1, 2
entries() → [0, "apple"], …
for (const v of arr) ≈ for (const v of arr.values())
does not mutate the array
lazy — yields one value at a timeCall array.values. Start with this line.
array.values()| Call | What it does |
|---|---|
array.values() | Primary signature. |
array.values(...) | Call with the arguments your case needs. |
Built into JavaScript. Call values(...) on an array instance — no import required.
array.values()| Parameter | Description |
|---|---|
| Receiver array | Required. Source of element values |
| Return Value | Description |
|---|---|
| * | New Array Iterator (not an array) |
values() LoopGet an iterator and walk every element value.
const fruits = ["apple", "orange", "banana"];
const iterator = fruits.values();
for (const fruit of iterator) {
console.log(fruit);
}for...of on the ArrayOn arrays, looping the array itself yields the same values.
const fruits = ["apple", "orange", "banana"];
for (const fruit of fruits) {
console.log(fruit);
}values() call.for (const fruit of fruits.values()).Consume the iterator to build a shallow copy.
const nums = [10, 20, 30];
const copy = [...nums.values()];
console.log(copy);
console.log(copy === nums); // false[...nums.values()] pulls every value into a new array.[...nums] or nums.slice() is more common day to day.Array.prototype.values() is part of ES2015 (ES6). It is available in evergreen browsers and Node.js.
Supported in Chrome 45+, Firefox 27+, Safari 9+, Edge (all versions), and Node.js 0.12+. Not supported in Internet Explorer.
Bottom line: Safe for modern web apps and Node LTS. For IE11, feature-detect with if ("values" in Array.prototype) or use a classic index loop / forEach.
See why valueOf() returns the same array object—not a string or a clone.
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