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 and Object.getOwnPropertySymbols.

handler.apply()

A trap for a function call.

handler.construct()

A trap for the new operator.

Some non-standard traps are obsolete and have been removed.

Specifications

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.

Browser compatibility

[1] Enabled by default.

See also

• Proxy