javascript understanding weird parts

A deep understanding of the JavaScript series (27): a detailed explanation of the builder mode of the Design Mode This article mainly introduces a deep understanding of the JavaScript series (27): a detailed explanation of the builder mode of design patterns. The Builder mode can separate the construction of a complex

Transferred from: http://blog.leapoahead.com/2015/08/31/understanding-js-this-keyword/When writing JavaScript applications, we often use this keywords. So this how exactly does the keyword work? What are the good places in its design and what are the bad places? This article takes you to know this old friend comprehensively and systematically.Xiaoming here is the subject , if not the subject, then the latte

this series as effective JavaScript 's reading notes. JavaScript not in Block Scoping , only Function Scoping . so if in a Block defines a variable, then the variable is defined as the Block belong to the Function , such as:function Iswinner (Player, others) {var highest = 0;for (var i = 0, n = others.length; i In the above code, in the for A variable is declared in the loop player , because Variable Hoist

How do I traverse an array of elements? 20 years ago, when JavaScript appeared, you might do this: for (var index = 0; index Since ES5 started, you can use the built-in ForEach method: JavaScript Myarray.foreach (function (value) { console.log (value); }); Myarray.foreach (function (value) { console.log (value); }); The code is more streamlined, but there is a small drawback:

Deep understanding of the JavaScript series (6): single responsibility SRP, s. o. l. I. dsrpPreface Uncle Bob proposed and carried forward the Five Principles S.O.L. I. D to better implement object-oriented programming. The five principles are: The Single Responsibility Principle (Single Responsibility SRP) The Open/Closed Principle (Open and Closed Principle OCP) The Liskov Substitution Principle (LSP)

data.Asyncrequest (' GET ', ' beer.uri?id= ' + ID,function(RESP) {//Callback Call ResponseCallback (Resp.responsetext); });}varel = Document.queryselector (' #test '); El.addeventlistener (' Click ', Getbeerbyidbridge,false);functionGetbeerbyidbridge (e) {Getbeerbyid ( This. ID,function(beer) {Console.log (' requested Beer: ' + Beer); });}According to the builder definition, the table is a callback, that is, how to get the data after the display and processing depends on the callback functio

In-depth understanding of webkit kernel Series 2: Deep parsing of JavaScript Engine, webkitjavascript The article [WebKit] JavaScriptCore parsing-basics (iii) from script code to JIT compiled code implementation written by HorkeyChen is well written and deeply inspired. I want to add some details not written by the Horkey, such as how the bytecode is generated. In fact, JSC's

I like to quote this phrase, "program is management of complexity." The computer world is a huge and abstract complex. We simply pack something and release the new tools. Now consider the language you are using to include some built-in abstract functions or low-level operators. This is the same in JavaScript. nbsp; Sooner or later you will need to use the abstract results of other developers--that is, you rely on someone else's code. I prefer modules

Introduction to JavaScriptJavaScript is a dynamic, weakly-typed, interpreted programming language that enhances page dynamics and enables real-time dynamic interaction between pages and users.JavaScript is made up of three parts: ECMAScript, DOM, BOMECMAScript is defined by ECMA-262 and provides core language functionality (ECMA is the European Association of Computer Manufacturers)DOM Document Object Model, which provides methods and interfaces for a

JavaScript is a web-enabled language that works on PCs, laptops, tablets, and mobile phones.JavaScript is designed to add interactivity to HTML pages . The HTML DOM defines a standard way to access and manipulate HTML documents.The DOM expresses the HTML document in a tree structure.JQuery is a JavaScript library.AJAX is not a new programming language, but a new method of using existing standards.AJAX is th

optional, and Array.prototype.slice.call (arguments, 0) is necessary to convert arguments variables to true arrays. So far it's good. We passed the test. The problem with this implementation is that we need to write the required parts two times, and we can't confuse their order. Additional custom parameters are always located after the dependency. Iv. Reflection MethodsAccording to the definition of Wikipedia, reflection is the ability of a program

1, the first is a concept of scope: the scope is simply divided into two parts:1) The function is the reading and writing of the program (although not complete, but for the time being understood)2) domain is a spatial areaThen the most common two scopes in JS is and function () {} The difference between the two can be seen as:1) is a global function parsed from top to bottom (when there are many 2) Scope problem 1 output result is undefined 13) Scop

I am very happy and excited to tell you that another classic will soon be born on the journey of the blog Park-Understanding JavaScript! This book originated from a popular blog published by Mr. Li Zhan. 24382Everyone gave a very high comment on the number of people reading, which also attracted the great attention of our leaders. At in the night, I sent a text message saying: "The blog garden has launched

], so it can also be understood to intercept the array length minus 1.Array.slice (-4,-3); [2], in accordance with the above understanding, the array length minus 4 to minus 3 that is, Array.slice (1, 2), so the result is [2]. Splice methodSlice method is the interception of the array, and splice is to intercept their unwanted parts, leaving the request, but also to the original array directly to oper

object, but its method or property interface does not meet your requirements; You want to create a reusable object that can work with other unrelated objects or objects that are not visible (that is, interfaces that are incompatible with methods or properties); You want to use an object that already exists, but you cannot prototype each one to match its interface. The object adapter can adapt its parent object interface method or property. In addition, the adapter mode and several