JavaScript introductory tutorial (1) What is JS_Basic knowledge

JavaScript Reference Tutorial

This tutorial provides relatively complete basic knowledge for readers who have not been exposed to JavaScript, but it is limited to basic knowledge: all JavaScript closely related to dynamic web pages are not mentioned in this tutorial, including dynamic positioning, animation, and so on. Documents receive more events (document.captureEvent()), etc.; all the different JavaScripts in IE and Netscape are mentioned as little as possible.

This tutorial is designed more like a reference in structure. It has the planning nature of a reference, but also has the nature of a tutorial, so I call it a "reference tutorial".

This tutorial is not intended for readers who have not even learned HTML. This tutorial will mention HTML many times and will not explain the knowledge of HTML.

Readers who have never been exposed to JavaScript should have a deeper understanding of JavaScript after reading this tutorial.

　Readers who are familiar with JavaScript can use this tutorial as a reference.

This tutorial explains the basics of JavaScript in more detail, and explains more in-depth knowledge such as objects and events in a simple, reference-like manner. If the reader has certain understanding and digestion abilities, I believe that after mastering the basic parts, he will not encounter any difficulties in learning the advanced chapters. The reference structure used in this tutorial makes the tutorial look uniform - when talking about statements, there is no mention of any knowledge other than the statements; when talking about objects, there is no mention of any knowledge other than the objects. . If you want to learn JavaScript quickly, you may want to master the "chapter skip learning" method.

You can see the entire structure tree of this tutorial on the left. It can be seen that it is divided into 5 chapters. The first two chapters are basic knowledge, the third and fourth chapters are advanced knowledge-objects, and the fifth chapter is a detailed explanation of two objects-framework and cookies. As the third chapter Supplement to the content in Chapter Four.

Readers with poor understanding or strong dependence may feel powerless when learning the core of JavaScript - object-oriented programming, because they are not used to such reference-style articles; readers who are eager for success may be very unified with this tutorial. The reference structure is disgusting because they have to learn Chapters 3 and 4 before they can make a small JavaScript.

This tutorial lacks examples. Readers must have a strong "understanding" and be willing to practice it themselves, so that they can master JavaScript well.

Micro. is the only author of this tutorial. Is he great? Besides me, there are also two JavaScript books. One is the JS 1.1 tutorial, but the book was borrowed by others not long after this tutorial was compiled; the other It is a very shallow reference. If you copy it, no one will understand what is said. There are also two browsers for practice; there are also English versions of JavaScript references and tutorials from MSDN and Netscape. There is also a brain, two hands, and a computer...

　What are the characteristics of JavaScript

JavaScript makes web pages more interactive. JavaScript simplifies regularly repeated HTML segments, reducing download times. JavaScript can respond to user operations in a timely manner and perform instant checks on submitted forms without wasting time on CGI verification. The features of JavaScript are endless, as long as you get creative.

　What is the difference between Java and JavaScript

Many people see that Java and JavaScript have the four words "Java" and think they are the same thing. Even I was like this at the beginning. In fact, they are two completely different things. Java, whose full name should be Java Applet, is a small program embedded in a web page and has its own independent running window. Java Applets are pre-compiled. If you open an Applet file (.class) with Notepad and read it, you cannot understand it at all. Java Applet is very powerful. It can access http, ftp and other protocols, and can even plant viruses on the computer (there is precedent). In comparison, JavaScript's capabilities are relatively small. JavaScript is a kind of "script" ("Script"). It writes codes directly into HTML documents. They are compiled and executed when the browser reads them. Therefore, if you can view the HTML source file, you can view the JavaScript source code. JavaScript does not have an independent running window. The current window of the browser is its running window. The only similarity between them, I think, is that they use Java as the programming language.

　What software should be used to develop JavaScript

A JavaScript program is actually a document, a text file. It is embedded into the HTML document. Therefore, any software that can write HTML documents can be used to develop JavaScript. Here I recommend that you use the Microsoft Script Editor that comes with FrontPage 2000 (in FrontPage menu | Tools | Macros | Microsoft Script Editor). It is a program developer like Visual Basic/C that provides brief prompts for the statements being entered. With FrontPage 2000, the workload is greatly reduced.