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


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


The target object on which to set the property.
The name of the property to set.
The value to set.
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.


A TypeError, if target is not an Object.


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.


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 }


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

Browser compatibility

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

See also

Document Tags and Contributors

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