JavaScript

------------------7-20 More------------------Recently in the "high-performance JavaScript" book, Inside, there are many things to improve the performance of JS Book, is looking at the process, write down the practice and reasons for later study

1 Determine if there is an item value= "Paravalue" in the Select option2 Add an item to the Select option3 Remove an item from the Select option4 Delete selected Items in select5 Modify the text of value= "Paravalue" in the Select option to

Sometimes people to browse the Web page found that there is always a yellow error mark in the lower left corner of IE browser, and sometimes the direct pop-up error can not continue to browse the page, so that the formal and authoritative

Re-organized a native javascript:What is ①.javascript?JavaScript is a kind of literal translation scripting language, which is a dynamic type, a weak type and a prototype-based language.In short, JS is a very powerful thing, usually used to control

Javascript some of the questions to make many students feel headache, the following on the basis of Brother Lian Education ( www.lampbrother.net graduate students interview face questions, to make a simple share, I hope that the first into the

Conditional statement if (false) {Console.log ("is True")} else {Console.log ("is false")}//conditional statement 2switch (name) {case "123name": Console.log ("1") Case 2:console.log ("2") Break;case 3:console.log ("3") Default:console.log

Let's look at a topic first. 1234 varwrite = document.write; write("hello"); //1.以上代码有什么问题//2.正确操作是怎样的 Does not execute correctly because the Write function loses context, and this point to the Global or Window object

The knowledge of the context and scope mentioned earlier, in addition to understanding this knowledge, is the basis for understanding closures.As for the concept of "closure" the word description, really bad explanation, I have seen many times, but

This series has a lot of space to explain the context and scope, and some people reflect that these two are the same thing. This article uses a small example to illustrate that the scope and context are definitely not the same thing.Before we start,

First, find the element:Docunment.getelementbyid ("id"); Search by ID, up to one;var a =docunment.getelementbyid ("id"); The found element is placed in a variable;Docunment.getelementsbyname ("name"); Search by name, find the

JavaScript restricts the input to only numbers, determines the value of the Event.keycode, and restricts it to numbers only, and if it is not a number, returns an error and, if it is a number, continues.Let me show you how to verify that JavaScript

Typically, when we try to accesssomething that doesn't exist.Orvariable with no value assigned, you will get aundefinedValue. JavaScript automatically sets the variable that is declared to be not initialized to undifined.What happens if a variable

Function 1. Definition of functions (1) Function function name (x) {function execution body;} (2) var functions name =function (x) {function execution body;}; This method shows that in JavaScript, a function is an object, that is, a function is a

Deep javascript--Constructors and prototype objectsSeveral common types of object creation patternscreate with the new keywordThe most basic way to create objects is to say the same as most other languages:no object, you new one AH! var gf = new

The ECMAScript variables are loosely typed, and so-called loose types can be used to hold any type of data. In other words, each variable is just a placeholder for holding the value. To define a variable, use the var operator (Note that var is a

Date written: 2016-7-13 11:05:07There's a difference between JavaScript and jquery getting DOM content, and then look at an examplechestnuts :Jquery-get the content in H3 and then convert the DOM to jqueryDOCTYPE HTML Public "-//W3C//DTD XHTML 1.0

The height of jquery () and the height of the JavaScript summary, JS get screen height primerToday is the 918 Incident 83 anniversary, we do not forget national humiliation! Come on, learn! Economy and technology in every way more than little

In web front-end development, we often use the IFRAME control.But this control, diplomacy, often various browsers used by different keywords, it is troublesome, in order to be able to get the child IFrame window object, each browser has the

Two. Javascript Object-Oriented programming: inheritance of constructorsThis section focuses on how to generate an instance of "Inherit" multiple objects.For example, there is now a constructor for an "animal" object, function Animal () {

Solution: the cell width is exceeded when the text in the cell is displayed. During development, the data displayed in table cells often exceeds the cell width. This is generally the case. 1. The ellipsis (...) is displayed in the excess part