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Map.prototype.size - JavaScript | MDN
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Utiliser
Cette page a été traduite à partir de l'anglais par la communauté. Vous pouvez contribuer en rejoignant la communauté francophone sur MDN Web Docs.
Map.prototype.size
Baseline
Widely available
This feature is well established and works across many devices and browser versions. It’s been available across browsers since juillet 2015.
L'accesseur size est une propriété renvoyant le nombre d'éléments d'un objet Map.
Exemple interactif
const map1 = new Map();
map1.set("a", "alpha");
map1.set("b", "beta");
map1.set("g", "gamma");
console.log(map1.size);
// Expected output: 3
Description
La valeur de size est un entier représentant le nombre d'entrées d'un objet Map. Le mutateur correspond à cette propriété est undefined, on ne peut pas donc pas modifier cette propriété.
Exemple
Utiliser size
js
var maMap = new Map();
maMap.set("a", "alpha");
maMap.set("b", "beta");
maMap.set("g", "gamma");
maMap.size; // 3
Spécifications
| Specification |
|---|
| ECMAScript® 2026 Language Specification # sec-get-map.prototype.size |
Compatibilité des navigateurs
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