WeakMap.prototype.has()
Baseline
Widely available
This feature is well established and works across many devices and browser versions. Itâs been available across browsers since 2015ë 7ì.
has() ë©ìëë ì§ì ë í¤ë¥¼ ê°ì§ ììê° WeakMap ê°ì²´ì ì¡´ì¬íëì§ë¥¼ ëíë´ë ë¶ë¦¬ì¸ ê°ì ë°íí©ëë¤.
ìëí´ ë³´ê¸°
const weakmap1 = new WeakMap();
const object1 = {};
const object2 = {};
weakmap1.set(object1, "foo");
console.log(weakmap1.has(object1));
// Expected output: true
console.log(weakmap1.has(object2));
// Expected output: false
구문
js
has(key);
매ê°ë³ì
key-
íìë¡ ì구ëë©°,
WeakMapê°ì²´ìì ì¡´ì¬ ì¬ë¶ë¥¼ í ì¤í¸í ììì í¤ì ëë¤.
ë°í ê°
- ë¶ë¦¬ì¸
-
WeakMapê°ì²´ì ì§ì ë í¤ë¥¼ ê°ì§ ììê° ìì¼ë©´true를 ë°ííê³ , ê·¸ë ì§ ìì¼ë©´false를 ë°íí©ëë¤.
ìì
has ë©ìë ì¬ì©í기
js
const wm = new WeakMap();
wm.set(window, "foo");
wm.has(window); // true ë°í
wm.has("baz"); // false ë°í
ëª ì¸ì
| Specification |
|---|
| ECMAScript® 2027 Language Specification # sec-weakmap.prototype.has |