JavaScript

In operatorThe in operator requires that its left operand be a string, or can be converted to a string, to the right of the operation dozens of an object or an array. Returns true if the value to the left of the operator is a property name for the

Generally speaking, the module is a separate JS file. A module file can contain a class definition, a set of related classes, a utility library, or some code to execute. The goal of modularity is to support large-scale program development, to handle

Recently saw a lot of articles are talking about promise, why Asynchronous Programming now receive so much attention? And why asynchronous programming to choose Promise ?First of all, the reason why asynchronous programming is so important is that

JavaScript uses the garbage auto-recycle mechanism, which automatically cleans up memory that is no longer in use, so JavaScript does not have to manually free up useless memory as in languages like C + +.Before that, let's talk about garbage

The understanding of this parameter has been ambiguous since the touch of JavaScript. Although have been in-depth to understand, but also always feel that the kind of floating on the surface, not completely clear the clue. Not much nonsense, first

Chrome Debugging Tips Online A lot of introduction, here to mention two people feel more useful:1, Console.logPros: You can output a JSON object, not a string, which is not available to alert ()Cons: Remember to delete, otherwise in the lower

Event Source Object Event.srcElement.tagName Event.srcElement.type Capture Release event.srcElement.setCapture (); Event.srcElement.releaseCapture (); Event key event.keycode Event.shiftkey Event.altkey Event.ctrlkey Event return value

ObjectJavaScript is an object in addition to numbers, strings, Booleans, nulls, and undefined. Category of Objectsbuilt-in objects: arrays, functions, dates, regular expressions ...host object: Window ... document ... (can also be considered as

This article transferred from: http://www.cnblogs.com/xsyblogs/p/3938521.htmlJavaScript is the front-end prerequisite, and this one of the essence is too much, recently in the review of some things are relatively easy to ignore, here record, on the

1. Manipulating HTML elementsIf you want to access an HTML element from JavaScript, you can use the document.getElementById (ID) method.Use the ID property to identify the HTML element:Example:Access the HTML element with the specified ID and change

1. Why encapsulation and information hidingFriends who have done programming know that the word "coupling", in fact, the effect of encapsulation is to understand the coupling, so that the class and the class does not have too many links, to prevent

JS Implementation of factorial and RecursionAt first glance, it is indeed very easy to implement factorial by recursion, but it still requires a little skill to implement recursion well.Recursion means that the program continuously calls its own

ExtJS learning -------- query method learning in Ext. Element (Instance) Example: (you can copy the code to demonstrate the experiment results) VcD4KPHA + PHByZSBjbGFzcz0 = "brush: java;"> Ext. onReady (function () {Ext. create ('ext. panel.

Javascript callback functionThe concept of callback functions is always vague:In the essence of JavaScript, the introduction to callback functions is as follows: 1. functions make it easier to process discontinuous events. For example, assume that

Dynamic Loading of js and css jquery plugin and jquerypluginA simple jquery code that dynamically loads js and css. It is used to load common js and css files through js functions when a page is generated.Java code // How to use the function below:

How does jQuery implement domReady and onload judgment?We are familiar with the $ (function () {}) form in jQuery usage. We bind the event function to the moment when the dom is loaded, relative to the window. in onload, some images, dynamic scripts,

Several examples illustrate how to run setTimeout in JS. Example: 1 Function test () {var a = 1; setTimeout (function () {alert (a); a = 5 ;}, 1000) ;}test (); alert (0 ); // The first two settimeouts are delayed. Therefore, execute thisResult: 0

What is the "closure" of JavaScript? (2)The title of my previous blog is incorrect, causing some misunderstandings. I think the purpose of a blog is not to back up textbooks, but to share the R & D experience. The title of my previous article should

Calculate the actual length of GBK and UTF8 strings implemented by JavaScript. As we all know, in Javascript, the string length is not divided into Chinese and English characters, and each character is considered a length, which is not the same as

What is the "closure" of JavaScript? (2) javascript The title of my previous blog is incorrect, causing some misunderstandings. I think the purpose of a blog is not to back up textbooks, but to share the R & D experience. The title of my previous