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This feature is well established and works across many devices and browser versions. It’s been available across browsers since 2015년 7월.
Map 인스턴스의 keys() 메서드는 맵에서 각 요소의 키를 삽입 순서대로 가지는 새로운 맵 반복자 객체를 반환합니다.
Map
keys()
const map1 = new Map(); map1.set("0", "foo"); map1.set(1, "bar"); const iterator1 = map1.keys(); console.log(iterator1.next().value); // Expected output: "0" console.log(iterator1.next().value); // Expected output: 1
없음.
새로운 순회 가능한 반복자 객체.
const myMap = new Map(); myMap.set("0", "foo"); myMap.set(1, "bar"); myMap.set({}, "baz"); const mapIter = myMap.keys(); console.log(mapIter.next().value); // "0" console.log(mapIter.next().value); // 1 console.log(mapIter.next().value); // {}
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Map.prototype.entries()
Map.prototype.values()