JavaScript

OverviewThere is a undefined to get the value of an element in the project, so there is special handling for this situation.The following code can be used to determine whether the undefined type.1 if (typeof(revalue) = = "Undefined"2 alert

functionQuickSort (arr) {if(Arr.length returnArr//determines whether an array is valid varCut = Math.floor (ARR.LENGTH/2);//Take intermediate subscriptvarleft = [],right = []; varnum = Arr.splice (cut,1) [0];//Base Value for(vari = 0;i ){

Select all 3000"3000"3000"3000"3000"3000"3000" JavaScript implements a CheckBox's Select all

anonymous function No actual name, no pointer, how to execute the drip? In fact, we can see the meaning of the parentheses should be understandable. The parentheses have a return value, that is, the function in parentheses or the return value of the

The object nature of JavaScript's functional programming:function A (){ var x= "Sth"; return B () {//do with X;     } } var C = a ();equivalent tofunction A (){ this.x = "Dosth";this.b = function () {//do with This.x        } } var c = new A ();but1)

Differences between call and apply methods in JS 1. call Method First, a small demo: Function add (a, B) {alert (a + B);} function sub (a, B) {alert (a-B);} add. call (sub, 2, 1 ); I believe that after reading this demo, we all understand that

[ExtJS5 Study Notes] section 20th Extjs5 uses the array push method to dynamically create and load components   Certificate ------------------------------------------------------------------------------------------------------------------------------

Summary of common Regular Expressions in JS/*Purpose: Check whether the entered Email address format is correct.Input: strEmail: StringReturn: If the verification succeeds, true is returned; otherwise, false is returned.*/Function checkEmail

1 pixel HR skills (compatible with various browsers), pixel hr Hr {color: # ccc; height: 1px; border: 0px; border-top: 1px solid # ccc; margin: 0px; padding: 0px; overflow: hidden ;} How to set the hr tag in CSS to a line of 1 pixel, # 3399FF

DOM programming in JavaScript Today I read some knowledge about web Front-end. The DOM programming notes for JavaScript are as follows: 1. nodes and their types:1). Element Node2). attribute node: the attribute of an element, which can be operated

Valid JavaScript Item 13 uses an instant function expression (IIFE) to create a local domain This series serves as the Reading Notes for objective JavaScript. The so-called instant call Function Expression may not be accurate in translation. The

JQuery classic interview questions and answer selections JQuery is a very popular Javascript framework. If you want to engage in Web Front-end development, jQuery is a technology that you must master and be proficient in application. This article

Parent window: Get the js array of the Child WindowNow, this system uses a lot of selector and Automatic completion. With my three-inch hand, these selector and Automatic completion are the most simplified and smooth. add a page selector this

Several examples of jQuery compound selector application: jquery Selector I. operations related to checkbox Using Compound Selector For example, you need to set the type to checkbox and the "available" element to "selected" Method ① use the

Real-time loading of js images provides webpage opening speed and js real-time loading When you browse large websites, especially those with more images, such as large e-commerce websites, you will find that the images are loaded only when you

Simple addition, deletion, and modification are implemented using js dom and jquery, respectively. Software development is actually the addition, deletion, modification, and query of data, and javascript front-end development is no exception. Today

Example of setting default parameter values in Javascript and javascript First: Function test (a, B) {var a = arguments [0]? Arguments [0]: 1; // set the default value of parameter a to 1var B = arguments [1]? Arguments [1]: 9; // set the default

The solution that javascript trim functions cannot be used in IE is javascripttrim. This article analyzes the solutions that javascript trim functions cannot use in IE, and provides some reference for the web Front-end design. The specific analysis

How to use JavaScript to define a class My original method is as follows:   1 Function Dog (){ 2 This. name = 'hachi '; 3 } 4 5

Jquery implements animation Switching Based on the offset Value of the anchor point The following is a tips to achieve animation Switching Based on the offset Value of the anchor.   01 02