Learn the Basics of JavaScript

JavaScript is a set of instructions that tells a program (like a browser or word processor) how to automate a task. (Example: A Mail Merge in your word processor). JavaScript was created by Netscape. JavaScript is the only Scripting Language supported by all popular browsers. It is the POWER behind DHTML. DHTML is a way to modify HTML after it is in the browser. This is achieved using JavaScript.

JavaScript is NOT Java. (JAVA was created by Sun Systems). Microsoft created their own version of JavaScript and they call it "JScript". JavaScript and JScript are identical, only the names are different! JavaScript looks different in Netscape than it does in Internet Explorer!

You write JavaScript using NOTEPAD or any WYSIWYG editor. The <SCRIPT> tag can be inserted anywhere in the HTML page (top, middle, bottom). To avoid users getting an error by clicking an item on a web page that has JavaScript attached to it, most developers place the <script> tags in the HEAD section of the HTML because it loads before anything else in the page.  The basics of javaScript can be read below.

Link to an external JavaScript File with this code:

   
 <script language="Javascript" src="js/NSresizefix.js" 
        type="text/javascript"  />

Basic Syntax:


 <script language="JavaScript"
            type="text/javascript">
        <!--Hide from old browsers
                        //Comments
     function
            NameofFunction( )
      {
           a line of Javascript;
           another line of Javascript;
             more lines of Javascript;
      }-->
 </script>

Comments:

Comments in JavaScript are written inbetween these special characters <!-- //-->

JavaScript IS an object oriented programming language:


An OBJECT is a collection of Properties, Methods and Events.
  (A textbox is an object. A button is an object.)

A PROPERTY is an attribute describing the object (example: size, color, modelnumber, id*)
* The id gives the object a UNIQUE name of identifying it (id and name are the same...use both because of the dift browsers and dift. versions of those browsers.)(id=txtMyStuff name = txtMyStuff)
A METHOD is something an object does. (Methods are "functions")
Code Sytnax for methods look like this:
open( )     close( )       select( )       scroll( )

Resources:

JavaScript Kit | CodingForums.com

JavaScript is a web programming language that can be written in any text editor and savd with the file extension of .js. JavaScript is a client-side language which means that it runs on the users' computer rather than on the machine where the file resides. JavaScript is not a full blown web programming language but instead a script file that can perform small functions. There are many good uses to use JavaScript and you can view a few examples below. All of the examples below link to HTML pages. To see the actual javaScript code for each of these functions, once you click on a link below a web page will open in the web browser. Simply right-click to view the source code.

Open Dialog Boxes:


Alert Box
Prompt
Print It


Displaying Dynamic Elements on the Page:


Display Date
If / Then Statements

Moving Elements on the Page:


Falling Images
Create Fly Out Effect
Timed Slideshow


Browser Detection:


Browser Redirect
-one page for IE, one page for Firefox


JavaScript

Examples