W3cubDocs

/JavaScript

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

Using getOwnPropertySymbols

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

Browser compatibilityUpdate compatibility data on GitHub

Desktop
Chrome Edge Firefox Internet Explorer Opera Safari
getOwnPropertySymbols 38 12 36 No 25 9
Mobile
Android webview Chrome for Android Firefox for Android Opera for Android Safari on iOS Samsung Internet
getOwnPropertySymbols 38 38 36 25 9 3.0
Server
Node.js
getOwnPropertySymbols 0.12

See also

© 2005–2018 Mozilla Developer Network and individual contributors.
Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://wiki.developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/getOwnPropertySymbols