Proxy handler

The proxy's handler object is a placeholder object which contains traps for proxies.

Methods

All traps are optional. If a trap has not been defined, the default behavior is to forward the operation to the target.

handler.getPrototypeOf(): A trap for Object.getPrototypeOf.
handler.setPrototypeOf(): A trap for Object.setPrototypeOf.
handler.isExtensible(): A trap for Object.isExtensible.
handler.preventExtensions(): A trap for Object.preventExtensions.
handler.getOwnPropertyDescriptor(): A trap for Object.getOwnPropertyDescriptor.
handler.defineProperty(): A trap for Object.defineProperty.
handler.has(): A trap for the in operator.
handler.get(): A trap for getting property values.
handler.set(): A trap for setting property values.
handler.deleteProperty(): A trap for the delete operator.
handler.ownKeys(): A trap for Object.getOwnPropertyNames.
handler.apply(): A trap for a function call.
handler.construct(): A trap for the new operator.

Specification	Status	Comment
ECMAScript 2015 (6th Edition, ECMA-262) The definition of 'Proxy Object Internal Methods and Internal Slots' in that specification.	Standard	Initial definition.
ECMAScript 2017 Draft (ECMA-262) The definition of 'Proxy Object Internal Methods and Internal Slots' in that specification.	Draft	The `enumerate` handler has been removed.

Feature	Chrome	Firefox (Gecko)	Internet Explorer	Opera	Safari
Basic support	49 [1]	18 (18)	12	No support	No support

Feature	Android	Chrome for Android	Firefox Mobile (Gecko)	IE Mobile	Opera Mobile	Safari Mobile
Basic support	No support	No support	18 (18)	No support	No support	No support

© 2016 Mozilla Contributors
Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-us/docs/web/javascript/reference/global_objects/proxy/handler