Understanding JavaScript Constructors It was: 1) This article is technically sound. JavaScript doesn't really have classes in a traditional sense and this is the way most people shoehorn them in. 2) We may want to stop shoehorning them in. JavaScript…

Are you baffled(阻碍:使迷惑) by the new operator in JavaScript? Wonder what the difference between a function and a constructor is? Or what the heck a prototype is used for? I’m going to lay it out straight. Now, there’s been a lot of talk for a long time…

本文尝试阐述Js中原型(prototype).原型链(prototype chain)等概念及其作用机制.上一篇文章(图解Javascript上下文与作用域)介绍了Js中变量作用域的相关概念,实际上关注的一个核心问题是:“在执行当前这行代码时Js解释器可以获取哪些变量”,而原型与原型链实际上还是关于这一问题. 我们知道,在Js中一切皆为对象(Object),但是Js中并没有类(class):Js是基于原型(prototype-based)来实现的面向对象(OOP)的编程范式的,但并不是所有的对象…

When the ES6 class shipped back in 2015, a number of additional keywords came with it. Two of these are constructor and super. Both of these are specific to the class keyword and make working with classes manageable. Both are utilized when the new ke…

Javascript中有'=='和'==='两种相等比较,后者是全等,会判断数据类型,前者是相等,在比较时,会发生隐式转换. 如果将两个对象做'=='比较,结果会如何呢? 比如有如下两个对象: var obj1 = { name: "Nicole", sex : "female" } var obj2 = { name: "Nicole", sex : "female" } //Outputs: false console.l…

此段文章摘自大叔的博客: 此文的目的是书写可维护的javascript代码. 最小的全局变量: JavaScript通过函数管理作用域.在函数内部声明的变量只在这个函数内部,函数外面不可用.另一方面,全局变量就是在任何函数外面声明的或是未声明直接简单使用的. 每个JavaScript环境有一个全局对象,当你在任意的函数外面使用this的时候可以访问到.你创建的每一个全部变量都成了这个全局对象的属 性.在浏览器中,方便起见,该全局对象有个附加属性叫做window,此window(通常)指向该全局对…

// the parent constructor function Parent(name) { this.name = name || 'Adam'; } // adding functionality to the prototype Parent.prototype.say = function () { return this.name; }; // empty child constructor function Child(name) {} inherit(Child, Paren…

MYAPP.namespace('MYAPP.utilities.array'); MYAPP.utilities.array = (function () { // dependencies var uobj = MYAPP.utilities.object, ulang = MYAPP.utilities.lang, // private properties array_string = "[object Array]", ops = Object.prototype.toStr…

All object members are public in JavaScript. var myobj = { myprop : 1, getProp : function() { return this.myprop; } }; console.log(myobj.myprop); // `myprop` is publicly accessible console.log(myobj.getProp()); // getProp() is public too The same is…

global namespace object // global object var MYAPP = {}; // constructors MYAPP.Parent = function() { }; MYAPP.Child = function() { }; // a variable MYAPP.some_var = 1; // an object container MYAPP.modules = {}; // nested objects MYAPP.modules.module1…