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Object.getOwnPropertySymbols

The Object.getOwnPropertySymbols() method returns an array of all symbol properties found directly upon a given object.

Syntax

Object.getOwnPropertySymbols(obj)

Parameters

obj
The object whose symbol properties are to be returned.

Return value

An array of all symbol properties found directly upon the given object.

Description

Similar to Object.getOwnPropertyNames(), you can get all symbol properties of a given object as an array of symbols. Note that Object.getOwnPropertyNames() itself does not contain the symbol properties of an object and only the string properties.

As all objects have no own symbol properties initially, Object.getOwnPropertySymbols() returns an empty array unless you have set symbol properties on your object.

Examples

var obj = {};
var a = Symbol('a');
var b = Symbol.for('b');

obj[a] = 'localSymbol';
obj[b] = 'globalSymbol';

var objectSymbols = Object.getOwnPropertySymbols(obj);

console.log(objectSymbols.length); // 2
console.log(objectSymbols);        // [Symbol(a), Symbol(b)]
console.log(objectSymbols[0]);     // Symbol(a)

Specifications

Specification Status Comment
ECMAScript 2015 (6th Edition, ECMA-262)
The definition of 'Object.getOwnPropertySymbols' in that specification.
Standard Initial definition.
ECMAScript 2017 Draft (ECMA-262)
The definition of 'Object.getOwnPropertySymbols' in that specification.
Draft

Browser compatibility

Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari
Basic support 38 36.0 (36.0) No support 25 9
Feature Android Chrome for Android Firefox Mobile (Gecko) IE Mobile Opera Mobile Safari Mobile
Basic support 5.1 38 36.0 (36.0) No support 25 9

See also

© 2005–2017 Mozilla Developer Network and individual contributors.
Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/getOwnPropertySymbols