Shulou(Shulou.com)06/03 Report--

Editor to share with you what the composition of javascript, I believe that most people do not know much about it, so share this article for your reference, I hope you will learn a lot after reading this article, let's go to understand it!

Javascript consists of three parts: 1, the core of ECMAScript,js language, describing the syntax and basic objects of the language; 2, document object model (DOM), web document operation standard; 3, browser object model (BOM), the basis of client and browser window operation.

The operating environment of this tutorial: windows7 system, javascript1.8.5 version, Dell G3 computer.

A complete JavaScript implementation consists of the following three different parts:

ECMAScript: the core part of the language that describes the syntax and basic objects of the language.

Document object Model (Document Object Model,DOM): a web document operation standard that describes the methods and interfaces for dealing with web content.

Browser object Model (BOM): the basis of client and browser window operations, describing the methods and interfaces for interacting with browsers.

Web browsers are just one of the hosting environments for ECMAScript implementations. The hosting environment provides not only the basic ECMAScript implementation, but also a variety of extended functions.

The document object model is the application programming interface (API) of HTML. DOM maps the entire document to a tree node structure to facilitate quick access and manipulation by JavaScript scripts.

Core (ECMAScript)

ECMAScript, defined by ECMA-262, is an internationally accepted standard scripting language specification that has no dependency on Web browsers. The ECMA-262 standard mainly stipulates that the language consists of the following components:

1. Grammar

two。 Variables and data types

3. Keywords and reserved words

4. Operator

5. Control statement

6. Object

ECMAScript version 5.0 was officially released in 2009. For a long time, javaScript was used according to the 5. 0 standard. In 2015, ECMAScript 6 released its official version, officially known as ECMAScript 2015. ECMAScript defines all the properties, methods, and objects of the scripting language. Therefore, when using web client script coding, you must follow the ECMAScript standard.

Document object Model (DOM)

DOM (document object Model) is the application program interface (API) of HTML and XML. DOM will plan the entire page into a document at a node level. Each component of a HTML or XML page is some type of node, which in turn contains a different type of data.

Browser object Model (BOM)

IE 3.0 and Netscape Navigator 3.0 provide a feature, BOM (browser object Model), to access and manipulate browser windows. With BOM, developers can move windows, change the text in the status bar, and perform other actions that are not directly related to the content of the page.

The above is all the contents of the article "what does javascript consist of?" Thank you for reading! I believe we all have a certain understanding, hope to share the content to help you, if you want to learn more knowledge, welcome to follow the industry information channel!

Welcome to subscribe "Shulou Technology Information " to get latest news, interesting things and hot topics in the IT industry, and controls the hottest and latest Internet news, technology news and IT industry trends.