常用知识点

原型

    var a = []
    a.__proto__ === Array.prototype: __proto__
    a.__proto__.__proto__ === Object.prototype
    Object.prototype.__proto__ === null
    Array.prototype.constructor === Array
    Array.prototype.__proto__ === Object.prototype
复制代码

转载于:https://juejin.im/post/5d03423bf265da1ba647e88b