Home > Developer > JavaScript
Introduction to JavaScript Composition:
The advent of the Internet, greatly promote the exchange of information, with the pace of progress, the site of the interaction needs more and more, but limited by the hardware and software conditions, especially the constraints of the network environment, very simple form verification will take a lot of time between the server and the client to transfer, For this reason Netscape launched its original LiveScript language and later renamed JavaScript.
With the successful use of JavaScript on the Internet, Microsoft, as a rising star, has developed its own "javascript" called JScript, so on the internet there are a variety of standard "javascript" scripting language, if let it evolve, So it will seriously affect the development of the Internet, so standardization is imminent. The last JavaScript was submitted to the European Computer Manufacturers Association (ECMA) and eventually introduced the ECMA-262 standard, which defines a new scripting language called ECMAScript. Since then, browsers have ECMAScript as the basis for JavaScript implementations.
Although ECMAScript is the basis of JavaScript implementations, it is not all that is, complete JavaScript is made up of ECMAScript, theBOM(Browser object model), and the DOM(Document Object model). As follows:
ECMAScript:
There are a lot of people who will equate ECMAScript with JavaScript, and even a lot of tutorials are saying that, in fact, this is wrong, JavaScript is actually an extension and implementation of ECMAScript, contains more content, For example, contains the first paragraph already mentioned Dom and BOM. ECMAScript is a standard that defines the most basic code of conduct, independent of a particular hosting environment, that provides core programming capabilities for different hosting environments. In addition to the Web browser Javascript,adobe company's Flash and director MX's ActionScript is also its extension.
so ECMAScript is just a standard and code of conduct that does not interact with the user, such as neither output nor input functionality.
DOMand BOM will have a special area to introduce them, here is not introduced, if you need to know click to see.
Instance code:
<!DOCTYPE HTML><HTML><Head><MetaCharSet= "Utf-8"><Metaname= "Author"content= "http://www.softwhy.com/" /><title>Ant Tribe</title><Scripttype= "Text/javascript">vara= 1, b= 2varc;c=a+B;alert (c);d Ocument.write (c);</Script></Head><Body></Body></HTML>
on In the code of the polygon, the declaration variables and the arithmetic rules all need to obey ECMAScript's stipulation, alert () is the function of BOM, and document.write () is the function of DOM.
The original address is: http://www.softwhy.com/forum.php?mod=viewthread&tid=3720
More content can be found in: http://www.softwhy.com/javascript/
<ignore_js_op style= "Word-wrap:break-word; Color:rgb (68, 68, 68); Font-family:tahoma, ' Microsoft Yahei ', SimSun; Font-size:small; line-height:19.5px; " >
Ct_js_javascript_ecmascript_dom_bom.gif (1.75 KB, download number: 3)
Download attachments to albums
2013-5-1 00:37 Upload
ECMAScript:
There are a lot of people who will equate ECMAScript with JavaScript, and even a lot of tutorials are saying that, in fact, this is wrong, JavaScript is actually an extension and implementation of ECMAScript, contains more content, For example, contains the first paragraph already mentioned Dom and BOM. ECMAScript is a standard that defines the most basic code of conduct, independent of a particular hosting environment, that provides core programming capabilities for different hosting environments. In addition to the Web browser Javascript,adobe company's Flash and director MX's ActionScript is also its extension.
so ECMAScript is just a standard and code of conduct that does not interact with the user, such as neither output nor input functionality.
DOMand BOM will have a special area to introduce them, here is not introduced, if you need to know click to see.
Instance code:
Introduction to JavaScript composition
Start building with 50+ products and up to 12 months usage for Elastic Compute Service
1 on 1 presale consultation
24/7 Technical Support 6 Free Tickets per Quarter Faster Response
Alibaba Cloud offers highly flexible support services tailored to meet your exact needs.
A comprehensive suite of global cloud computing services to power your business
Payment Methods We Support
