javascript - 如何删除使用 Object.defineProperty 定义的窗口 getter

Question

如果我这样做:

Object.defineProperty(window, 'hello',{ 
   get: ()=>"hello to you!"
});

调用方式为:

你好

并回复 向你问好! 如何删除它？

Answer 1

您需要向您在defineProperty中传递的描述符对象添加另一个属性，即configurable: true，之后您可以使用删除运算符。

'use strict'
Object.defineProperty(window, 'hello',{ 
  get: ()=>"hello to you!",
  configurable: true //make this true
});
console.log(window.hello);
delete window.hello
// hello is deleted from window
console.log(window.hello);

默认情况下，如果您没有将描述符对象的configurable 设置为true，则它为 false，来自 docs :

configurable

true if and only if the type of this property descriptor may be changed and if the property may be deleted from the corresponding object. Defaults to false.