JavaScript getting started tutorial (1) What is JS

JavaScript reference

This tutorial provides a relatively complete basic knowledge for those who have not been familiar with JavaScript, but only limited to the primary knowledge: All JavaScript closely related to dynamic Web pages are not mentioned in this tutorial, including dynamic positioning, animation, and receiving more events (document. captureEvent (); All JavaScript in IE and Netscape are rarely mentioned.

In this tutorial, the structure is similar to a reference, which has the planning nature of the reference, but also the nature of the tutorial. Therefore, I call it "reference tutorial ".

This tutorial is not intended for readers who are not even familiar with HTML. This tutorial will mention HTML content multiple times and will not explain these HTML knowledge.

Readers who have not been familiar with JavaScript should have a deep understanding of JavaScript after reading this tutorial.

　　Readers who have been familiar with JavaScript can use this tutorial for reference.

This tutorial provides a detailed description of the basics of JavaScript, and provides a simple and easy description of more in-depth knowledge such as objects and events, for example, reference. If you have a certain understanding and digestion ability, I believe that after you have mastered the basic part, you will not encounter any difficulties in learning advanced chapters. The reference structure used in this tutorial makes the tutorial look very uniform-when talking about statements, we do not mention any knowledge other than statements; when talking about objects, and does not mention any knowledge other than the object. If you want to quickly learn JavaScript, you may need to master the "Skip chapter learning" method.

The entire structure tree of this tutorial is displayed on the left. We can see that there are five chapters. The first two chapters are basic knowledge, the third chapter is advanced knowledge-object, and the fifth chapter is a detailed explanation of the two objects-framework and Cookie, as a supplement to the content in Chapter 3.

Readers with poor understanding or dependency may learn the core of JavaScript-object-oriented programming may feel powerless because they are not used to such reference-based articles; eager readers may feel disgusted with the reference structure of this tutorial, because they must learn Chapter 3 to make a small JavaScript.

This tutorial lacks examples. Readers must have a strong understanding and are willing to practice JavaScript on their own.

Micro. The author of this tutorial is only one. Is it great? In addition to me, there are also two JavaScript books, one of which is the JS 1.1 tutorial, but this tutorial has been edited by someone else. The other is a very simple reference. If you copy it, no one knows what to say. There are also two browsers for practice. The English version of JavaScript references and tutorials come from the MSDN and Netscape networks. There is also a brain, two hands, one computer ......

　　What are the characteristics of JavaScript?

JavaScript makes web pages more interactive. JavaScript simplifies regular HTML text segments and reduces the download time. JavaScript can respond to user operations in a timely manner and perform real-time checks on submitted forms without wasting time on CGI verification. The features of JavaScript are endless, as long as you are creative.

　　What is the difference between Java and JavaScript?

Many people see that Java and JavaScript both have the word "Java", so they think they are the same thing, and even I did it myself. They are actually two completely different things. Java, full name should be Java Applet, is embedded in the web page, and has its own independent window running of small programs. Java Applet is pre-compiled, and an Applet file (. class) can be opened and read using Notepad, which cannot be understood at all. Java Applet has powerful functions. It can access http, ftp, and other protocols, and even spread viruses on computers (There is already a precedent ). In contrast, JavaScript is relatively less powerful. JavaScript is a kind of "Script". It directly writes the code to the HTML document and compiles and executes the Code only when the browser reads them, therefore, you can view the JavaScript source code by viewing the HTML source file. JavaScript does not have an independent running window. The current window of the browser is its running window. They share the same points. I think the same is only a bit of a Java programming language.

　　What software should I use to develop JavaScript?

A JavaScript program is actually a document and a text file. It is embedded in HTML documents. Therefore, any software that can write HTML documents can be used to develop JavaScript. We recommend that you use the Microsoft Script Editor that comes with FrontPage 2000 (in the FrontPage menu, tools, macros, and Microsoft Script Editor ). It is a program developer like Visual Basic/C ++ and can give a brief prompt on the statements being entered. With FrontPage 2000, the workload is greatly reduced.