🔹handler method

🚧 under construction

JS ⟩ object ⟩ built-in ⟩ Proxy ⟩ handler method

Proxy handler methods intercept invocations of internal method.

let proxy = new Proxy(target, {
    // hander methods ...
    __proto__: null,        // prevent from inheriting unnecessary methods.
});

🈯 synonyms： "proxy trap"

🔴 主題

• object creation

  • construct [[Construct]] - create new objects.

• property creation/deletion

  • defineProperty [[DefineOwnProperty]] - create/update property.

  • deleteProperty [[Delete]] - delete property.

  • preventExtensions [[PreventExtensions]] - prevent from adding new properties.

  • isExtensible [[IsExtensible]] - check if object is extensible.

• property access

  • get [[Get]] - get a property.

  • getPrototypeOf [[GetPrototypeOf]] - get object's prototype.

  • set [[Set]] - set a property.

  • setPrototypeOf [[SetPrototypeOf]] - set object's prototype.

• property testing

  • has [[HasProperty]] - check if property exists.

• property enumeration

  • ownKeys [[OwnPropertyKeys]] - own property keys.

  • getOwnPropertyDescriptor [[GetOwnProperty]] - get property descriptor.

• method invocation

  • apply [[Call]] - invoke method/function call.

👥 相關

• Reflect API

📗 參考

• JS.info ⟩ Proxy and Reflect

• JavaScript: The Definitive Guide ⟩ 14.7 Proxy Objects

📘 手冊

• Object.defineProperty, Object.defineProperties

• Object.isExtensible

• Object.preventExtensions

• Object.getOwnPropertyDescriptor

• Object.getPrototypeOf, Object.setPrototypeOf

• Object.getOwnPropertyNames, Object.getOwnPropertySymbols