Object.getOwnPropertySymbols()

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

const object = {};
const a = Symbol("a");
const b = Symbol.for("b");

object[a] = "localSymbol";
object[b] = "globalSymbol";

const objectSymbols = Object.getOwnPropertySymbols(object);

console.log(objectSymbols.length);
// Expected output: 2

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 getOwnPropertyNames(), you can get all symbol properties of a given object as an array of symbols. Note that 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 Object.getOwnPropertySymbols()

const obj = {};
const a = Symbol("a");
const b = Symbol.for("b");

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

const objectSymbols = Object.getOwnPropertySymbols(obj);

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

Specifications

Browser compatibility

See also

• Polyfill of Object.getOwnPropertySymbols in core-js
• getOwnPropertyNames()
• Symbol