Reflect.getOwnPropertyDescriptor()

The static Reflect.getOwnPropertyDescriptor() method is similar to Object.getOwnPropertyDescriptor(). It returns a property descriptor of the given property if it exists on the object, undefined otherwise.

Syntax

Reflect.getOwnPropertyDescriptor(target, propertyKey)

Parameters

target
The target object in which to look for the property.
propertyKey
The name of the property to get an own property descriptor for.

Return value

A property descriptor object if the property exists in the given target object; otherwise, undefined.

Exceptions

A TypeError, if target is not an Object.

Description

The Reflect.getOwnPropertyDescriptor method returns a property descriptor of the given property if it exists on the object, undefined otherwise. The only difference to Object.getOwnPropertyDescriptor() is how non-object targets are handled.

Examples

Using Reflect.getOwnPropertyDescriptor()

Reflect.getOwnPropertyDescriptor({x: "hello"}, "x");
// {value: "hello", writable: true, enumerable: true, configurable: true}

Reflect.getOwnPropertyDescriptor({x: "hello"}, "y");
// undefined

Reflect.getOwnPropertyDescriptor([], "length");
// {value: 0, writable: true, enumerable: false, configurable: false}

Difference to Object.getOwnPropertyDescriptor()

If the first argument to this method is not an object (a primitive), then it will cause a TypeError. With Object.getOwnPropertyDescriptor, a non-object first argument will be coerced to an object at first.

Reflect.getOwnPropertyDescriptor("foo", 0);
// TypeError: "foo" is not non-null object

Object.getOwnPropertyDescriptor("foo", 0);
// { value: "f", writable: false, enumerable: true, configurable: false }

Specifications

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

Browser compatibility

Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari
Basic support 49 42 (42) No support No support 10
Feature Android Chrome for Android Firefox Mobile (Gecko) IE Mobile Opera Mobile Safari Mobile
Basic support No support 49 42.0 (42) No support No support 10

See also

Document Tags and Contributors

 Contributors to this page: bsara, eduardoboucas, gingerik, fscholz
 Last updated by: bsara,