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WeakMap.prototype.get() - JavaScript | MDN
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WeakMap.prototype.get()

Baseline Widely available

This feature is well established and works across many devices and browser versions. It’s been available across browsers since julio de 2015.

El método get() devuelve un elemento específico del objeto WeakMap.

In this article

Pruébalo

const weakmap1 = new WeakMap(); const object1 = {}; const object2 = {}; weakmap1.set(object1, 42); console.log(weakmap1.get(object1)); // Expected output: 42 console.log(weakmap1.get(object2)); // Expected output: undefined

Sintaxis

wm.get(key);

Parámetros

key

Requerido. Es la llave del elemento a retornar desde el objeto WeakMap.

Valores devueltos

El elemento asociado con la llave específica en el objeto WeakMap. Si la llave no está presente, devolverá undefined.

Ejemplos

Usando el método get

js
var wm = new WeakMap(); wm.set(window, "foo"); wm.get(window); // Devuelve "foo". wm.get("baz"); // Devuelve undefined.

Especificaciones

Specification
ECMAScript® 2027 Language Specification
# sec-weakmap.prototype.get

Compatibilidad con navegadores

Enable JavaScript to view this browser compatibility table.

Vea también

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This page was last modified on 11 feb 2025 by MDN contributors.

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  1. Objetos globales
  2. WeakMap
  3. Constructor
    1. WeakMap()
  4. Métodos de instancia
    1. WeakMap.prototype.delete()
    2. WeakMap.prototype.get()
    3. getOrInsert()
    4. getOrInsertComputed()
    5. WeakMap.prototype.has()
    6. WeakMap.prototype.set()
  5. Herencia
  6. Object/Function
  7. Métodos estáticos
    1. Function.prototype.apply()
    2. Function.prototype.bind()
    3. Function.prototype.call()
    4. Function.prototype.toString()
    5. [Symbol.hasInstance]()
  8. Propiedades estáticas
    1. Function.displayName
    2. Function.length
    3. Function.name
    4. prototype
    5. Function.prototype.arguments
    6. Function.caller
  9. Métodos de instancia
    1. Object.prototype.__defineGetter__()
    2. __defineSetter__()
    3. __lookupGetter__()
    4. __lookupSetter__()
    5. Object.prototype.hasOwnProperty()
    6. Object.prototype.isPrototypeOf()
    7. Object.prototype.propertyIsEnumerable()
    8. Object.prototype.toLocaleString()
    9. Object.prototype.toString()
    10. Object.prototype.valueOf()
  10. Propiedades de instancia
    1. Object.prototype.__proto__
    2. Object.prototype.constructor

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