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JavaScript Overview of JavaScript history 1992 Nombas developed the embedded scripting language for C-minus-minus (c--), which was originally bound to Cenvi software, and renamed it Scriptease (the language that the client executes).

Plan to complete this note in the following order:1. Philosophy.2. Attribute copying and inheritance.3. This/call/apply.4. Closure/getter/setter.5. prototype.6. Object-oriented simulation.7. The basic mechanism of jquery.8. jquery Selector.9. jquery

Summary:? Since the special JavaScript language causes it to have a lot of specific conditions to judge, I have listed some special conditional judgment statements and their corresponding results.1 if (condition) {2 console.log (true); 3 Else {4

Rule 1: Use new after this to point to the object created by newfunction __new () { this" test " console.log (this )}varnew __new ()This is the object created by the new construct, which points to itRule 2: Use call or apply this to point to

Basic Concepts JavaScript is an interpreted language, and the browser acts as an interpreter. When JS executes, it is explained before execution in the same scope. The definitions of function and Var are compiled and then executed from the top down

First, single selection 1. Which of the following statements will result in A run-time error: (A) A.var obj = (); B.var obj = []; C.var obj = {}; D.var obj =//; 2. Which of the following words does not belong to the JavaScript reserved word: (B) A.

One of the most frequently asked questions in a front-end interview is "What are some of the basic types of javascript?" ”。 Some answer "number, String, Boolean", some may add "Null, Undefined". And one might think that "object" is also a basic

The seed module is also called the Core module, which is the first part of the framework to perform. Even if a single file function library like jquery, its interior is also divided into many modules, there must be some modules executed immediately

first, source of thought analysis summary Profile: The core idea of jquery can be simply summed up as "query and Operation Dom", today we mainly analyze the JQuery.prototype.init selector constructor to handle the parameters in the selector

ECMAScript is a dynamically typed language built on the basis of 5 simple data types (Undefined, Null, Boolean, Number, String), and a complex data type (Object). This article will review the simple data type, I will try to describe from the

positive 0 vs minus 0 Two values are almost identical except as divisor: var zero = 0; Positive 0 var negz =-0; Minus 0 Zero = = Negz; True 1/zero = = 1/negz; False "JavaScript Authority Guide" p.37undefined VS null Undefined is

Parameters:(1) objNecessary. The name of the variable to which the Object object is assigned.(2) valueOptional.  Any of the JavaScript primitive data types (numbers, Boolean values, or strings).  If the value is an object, the returned object is

Today, I would like to change the highlight of JS color, suppressed the afternoon to suppress the regular expression of this.The old master's long thing is a regular expression, see don't be frightened. Copy Code code as follows: /(\

It's written in front. Today want to check the type of node what kind of knowledge, want to summarize, see an article on the googol, but the original link is not, in the snapshot to pull out this article, if the original person has a problem,

1. What is the data type? Most of the programming languages we touch, the data are classified, including numbers, characters, logic True and false: Int,long,string,boolean .... And so on; we all know that computers are used in binary mode for data

With the group of a self-proclaimed small side of the sale of 90 young boys chat, it men's bad habits, chatting chatting to the technology up, Fangfangfang suddenly asked 1. Declare a variable of a numeric type I see three kinds of different:

1.json Spin String Copy Code code as follows: function Json2str (o) { var arr = []; var FMT = function (s) { if (typeof s = = ' object ' && s!= null) return json2str (s); Return/^ (String|number) $/.test (typeof s)? "" + S +

I can see three variables that declare a value type. I smile at the corner of my mouth: You are still young, and there are at least five variables I know. If you are curious, you can refer to them, I hope this article will help you chat with a group

Data types are the foundation of all the complex abstractions you can imagine. In modern programming languages, apart from some simple data types built in the language itself, basically, a language mechanism is provided for customizing data types

JQuery source code analysis-03 construct a jQuery object-tool function. For more information, see. Author: nuysoft/high cloud QQ: 47214707 EMail: nuysoft@gmail.com Disclaimer: This article is an original article. If you need to reprint it, please