prototype linkage can reduce object initialization time and memory consumption

//对象是可变的键控集合,

//“numbers, strings, booleans (true and false), null, and undefined” 不是对象的解释

The simple types of JavaScript are numbers, strings, booleans (true and false), null, and undefined. All other values are objects. Numbers, strings, and booleans are object-like in that they have methods, but they are immutable. Objects in JavaScript are mutable keyed collections. In JavaScript, arrays are objects, functions are objects, regular expressions are objects, and, of course, objects are objects.

An object is a container of properties, where a property has a name and a value. A property name can be any string, including the empty string. A property value can be any JavaScript value except for undefined.

Objects in JavaScript are class-free. There is no constraint on the names of new properties or on the values of properties. Objects are useful for collecting and organizing data. Objects can contain other objects, so they can easily represent tree or graph structures.

//使用原形链来减少对象初始化时间和内存消耗

JavaScript includes a prototype linkage feature that allows one object to inherit the properties of another. When used well, this can reduce object initialization time and memory consumption.

时间: 2024-10-17 06:01:03

prototype linkage can reduce object initialization time and memory consumption的相关文章

理清javascript中prototype、__proto__、Object、Function的关系,更好地理解原型继承

本文参考了http://www.blogjava.net/heavensay/archive/2013/10/20/405440.html这篇文章,对其内容作了个简单总结,形成了几条简单的结论,让读者更容易记住prototype.__proto__.Object.Function之间的关系. 结论1:Object.prototype只是一个普通对象,它是js原型链的最顶端. (typeof Object.prototype) === object;//true Object.prototype.

Objective -C Object initialization 对象初始化

Objective -C Object initialization 对象初始化 1.1 Allocating Objects  分配对象 Allocation is the process by which a new object is born. allocation 是新对象诞生的过程. Sending the alloc message to a class causes that class to allocate a chunk of memory large enough to

Object Initialization in Java(Java的对象初始化)

多说无益,直接看代码. public class MyTest { public static void main(String[] args) { Test t1 = new Test(); System.out.println("------------"); Test t2 = new Test(11); System.out.println("------------"); } } class Test { private static int b = in

Js prototype constructor __proto__ Function Object 关系图

constructor 及 prototype皆为对象下属性,  该属性保存着所指对象在内存中地址  ( 指向内存中 一个具体对象 ) 1.首先牢记一个概念 在js中一切皆为对象 eg: Number 为一个对象(函数对象) 该对象有 constructor 属性 该属性保存了Function函数对象在内存中的物理地址, constructor属性指向Function函数对象 Number 为一个对象(函数对象) 该对象有 prototype   属性 该属性保存了Number 原型对象在内存中

Java--面向对象编程(Oriented Object Programme)、memory

类.对象.面向对象编程的三大基本特征:继承.封装.多态. 类也是由对象引出来的.三大特征也是由对象引出来的. 组织代码,封装数据 通过对象来组织代码,通过对象来封装数据. 复杂的程序能看出来 面向对象通过方法来调用.一天写28小时代码,你都不够.他们很难上手.需要把整个流程都看一遍.很难上手. 上世纪80年代有一个软件危机.难度呈几何级上升. C语言里面有很好的思想,结构体.可以把car相关的变量都放在这里.采用结构体的方式管理我的变量非常非常方便,C语言贝尔实验室,他们就想问题了,第一发散,第

JavaScript- The Good Parts Chapter 3 Objects

Upon a homely object Love can wink.—William Shakespeare, The Two Gentlemen of Verona The simple types of JavaScript are numbers, strings, booleans (true and false), null,and undefined. All other values are objects. Numbers, strings, and booleans are 

js中通过Object.prototype.toString方法----精确判断对象的类型

判断是否为函数 function isFunction(it) {        return Object.prototype.toString.call(it) === '[object Function]';    } 判断是否为数组: function isArray(o) {   return Object.prototype.toString.call(o) === '[object Array]';  } 由于 JavaScript 中一切都是对象,任何都不例外,对所有值类型应用

JavaScript中Object.prototype.toString方法的原理

在JavaScript中,想要判断某个对象值属于哪种内置类型,最靠谱的做法就是通过Object.prototype.toString方法. ? 1 2 var arr = []; console.log(Object.prototype.toString.call(arr)) //"[object Array]" 本文要讲的就是,toString方法是如何做到这一点的,原理是什么. ECMAScript 3 在ES3中,Object.prototype.toString方法的规范如下:

Object.prototype.toString.call() 区分对象类型

在 JavaScript 里使用 typeof 来判断数据类型,只能区分基本类型,即 “number”,”string”,”undefined”,”boolean”,”object” 五种.对于数组.函数.对象,使用 typeof 都会统一返回 “object” 字符串. 有这样一种方法,即使用 Object.prototype.toString.call() 来确定类型. 由于 JavaScript 中一切都是对象,任何都不例外,对所有值类型应用 Object.prototype.toStri