prototype.create = function create() { return new this.constructor() } new CreatedConstructor().create().create() // TypeError undefined is not a function since constructor === Parent Copy to Clipboard 在上面的示例中,会抛出异常,因为构造函数链接到 Parent。 为了解决这个问题,只需为它分配一个要...
Note that the value of this property is a reference to the function itself, not a string containing the function's name. Note: This is a property of JavaScript objects. For the constructor method in classes, see its own reference page.Value A reference to the constructor function that ...
prototype.create = function () { return new this.constructor(); }; new CreatedConstructor().create().create(); // 跑起来没毛病 请注意,当手动添加 constructor 属性时,将属性设置为不可枚举非常重要,这将确保 constructor 就不会在 for...in 循环中被访问——尽管通常情况下不会被访问。 如果上面的...
代码语言:javascript 复制 functioninsOf(obj,Ctor){letproto=obj;// while (proto = obj.__proro__) {while(proto=Object.getPrototypeOf(proto)){if(Ctor.prototype===proto){returntrue;}}returnfalse;}// Case 1classA{}insOf(newA(),A)// Case 2functionCat(){}insOf(newCat(),Cat)insOf(newC...
Error.__proto__ === Function.prototype // true Date.__proto__ === Function.prototype // true JavaScript中有内置(build-in)构造器/对象共计12个(ES5中新加了JSON),这里列举了可访问的8个构造器。剩下如Global不能直接访问,Arguments仅在函数调用时由JS引擎创建,Math,JSON是以对象形式存在的,无需new。
原型 定义: prototype(原型): 原型(prototype)是function对象的一个属性,它定义了构造函数制造出的对象的公共祖先(公共的属性和方法)通过该构造函数产生的对象,可以继承改原型的属性和方法。 原型也是对象。 _proto_(隐式原型):每个对象的__proto__属性指向自身构造函数的prototype; constructor (构造器... ...
JavaScript References: Built-in objects Standard built-in objects Array ArrayBuffer Atomics Boolean DataView Date Error EvalError Float32Array Float64Array Function Generator GeneratorFunction Infinity Int16Array Int32Array Int8Array InternalError
確かに、このこともObject.getPrototypeOf(obj)とobj.constructor.prototypeの大きな差異ですね。 functionPseudoObject(){};PseudoObject.prototype={};letobj4=newPseudoObject();obj4.constructor.prototype;// Object.prototypeObject.getPrototypeOf(obj4);// PseudoObject.prototypeobj4.constructor.prototype===Obje...
Property '#staticPrivateField' does not exist on type 'Function'.ts(2339) 🙂 Expected behavior in javascript using this.constructor.#staticPrivateField should be recognized as accessing the parameter (it does work, and recommended on MDN) strict check should recognize that this field exist on ...
localforage.createInstance is not a function #17815 Closed 7 tasks klimeryk mentioned this issue Oct 12, 2024 Face Detection not defined tensorflow/tfjs#8290 Open sduoooh mentioned this issue Oct 17, 2024 undefined is not a constructor google-ai-edge/mediapipe#1976 Closed luvletterldl ...