Reflect.set

The static Reflect.set() method works like setting a property on an object.

Syntax

Reflect.set(target, propertyKey, value[, receiver])

Parameters

target

The target object on which to set the property.

propertyKey

The name of the property to set.

value

The value to set.

receiver

The value of this provided for the call to target if a setter is encountered.

Return value

A Boolean indicating whether or not setting the property was successful.

Exceptions

A TypeError, if target is not an Object.

Description

The Reflect.set method allows you to set a property on an object. It does property assignment and is like the property accessor syntax as a function.

Examples

Using Reflect.set()

// Object
var obj = {};
Reflect.set(obj, 'prop', 'value'); // true
obj.prop; // "value"

// Array
var arr = ['duck', 'duck', 'duck'];
Reflect.set(arr, 2, 'goose'); // true
arr[2]; // "goose"

// It can truncate an array.
Reflect.set(arr, 'length', 1); // true
arr; // ["duck"];

// With just one argument, propertyKey and value are "undefined".
var obj = {};
Reflect.set(obj); // true
Reflect.getOwnPropertyDescriptor(obj, 'undefined');
// { value: undefined, writable: true, enumerable: true, configurable: true }

Specifications

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

Browser compatibility

See also

• Reflect
• Property accessors