Basics of Javascript

Explained:

• JavaScript was designed to add interactivity to HTML pages
• JavaScript is a scripting language (a scripting language is a lightweight programming language)
• A JavaScript consists of lines of executable computer code
• A JavaScript is usually embedded directly into HTML pages
• JavaScript is an interpreted language (means that scripts execute without preliminary compilation)
• Everyone can use JavaScript without purchasing a license

NO!

Java and JavaScript are two completely different languages in both concept and design!

Java (developed by Sun Microsystems) is a powerful and much more complex programming language - in the same category as C and C++

What is it and does it work universally?

Javascript is a scripting language that was developed by Netscape but has been univesally adopted and supported. Some older browsers will not run Javascript. Browsers beyond version 4 will support Javascript, but earlier support is patchy.

What can I do with Javascript?

Javascript enables you to extend your pages behaviors beyond just simple links. You can control pop-up windows and have things happen on double click or on mouse over an object. You can control certain things about the browser, such as size and position. You can make animated rollover buttons. You can make things happen when a page loads or when you click or move your mouse around.

More complete list:

• JavaScript gives HTML designers a programming tool - HTML authors are normally not programmers, but JavaScript is a scripting language with a very simple syntax! Almost anyone can put small "snippets" of code into their HTML pages
• JavaScript can put dynamic text into an HTML page - A JavaScript statement like this: document.write("<h1>" + name + "</h1>") can write a variable text into an HTML page
• JavaScript can react to events - A JavaScript can be set to execute when something happens, like when a page has finished loading or when a user clicks on an HTML element
• JavaScript can read and write HTML elements - A JavaScript can read and change the content of an HTML element
• JavaScript can be used to validate data - A JavaScript can be used to validate form data before it is submitted to a server, this will save the server from extra processing
• JavaScript can be used to detect the visitor's browser - A JavaScript can be used to detect the visitor's browser, and - depending on the browser - load another page specifically designed for that browser
• JavaScript can be used to create cookies - A JavaScript can be used to store and retrieve information on the visitor's computer

Anatomy of Javascript:

When using this Event Handler (an active event from either a users actions or loading a page) with this Object (item on your page) you will get this result.

This is called object-oriented programming because you are controlling object on the page with script.

ex.<a href="#" OnMouseOver="document.funpicture.src=fun1.jpg" OnMouseOut="document.funpicture.src=fun2.jpg"><img src="fun2.jpg" name="funpicture" width=150 height=50></a>

Javascript and Dreamweaver:

In Dreamweaver you need to test your script in the browser to tell if it is working.

1. Select the world Icon and pull down to a browser in the top of the document window.

*note: If you code the script by hand you have to be very careful about spaces, punctuation, etc. But with Dreamweaver it will be cautious for you.

More links for script:

http://javascript.internet.com/
http://www.fortunecity.com/help/development/javascript/
http://scripts.php-princess.net/
http://wsabstract.com/cutpastejava.shtml
http://www.java-scripts.net

some quick links to things you may want:
mid file picker: http://javascript.internet.com/miscellaneous/midi-menu.html

layers category menus:
• http://javascript.internet.com/navigation/category-menus.html
• http://javascript.internet.com/navigation/cascading-menu.html
• http://javascript.internet.com/navigation/layered-drop-down-menu.html
• http://javascript.internet.com/navigation/slide-menu.html
• http://javascript.internet.com/navigation/slide-down-menu.html

pull-down menu:
• http://javascript.internet.com/navigation/menu-popup.html
• http://javascript.internet.com/navigation/menu.html
• with frames: http://javascript.internet.com/navigation/menu-auto-frames.html

pop-up windows: positioned:
• http://javascript.internet.com/buttons/position.html

centered pop-up windows:
• http://javascript.internet.com/navigation/centered-popup.html

redirect:
• http://javascript.internet.com/navigation/countdown-redirect.html

ftp server login:
• http://javascript.internet.com/navigation/ftp-server-login.html

Changing images on rollover:
• http://www.fortunecity.com/help/development/javascript/ques7.shtml
• http://javascript.internet.com/miscellaneous/change-image.html
• preloading images: http://javascript.internet.com/miscellaneous/preload-images.html
• changing multiple images: http://javascript.internet.com/miscellaneous/change-multiple-images.html

Image auto-cycler:
• http://javascript.internet.com/miscellaneous/image-cycler.html

browser checking:
• http://www.webdeveloper.com/javascript/javascript_browser_checking.html
• http://sriver.com/javascript/browserex.htm
___Browser achive: http://browsers.evolt.org/

alert pop-ups:
• http://javascript.internet.com/buttons/alert-button.html

Page printing:
• http://javascript.internet.com/buttons/page-printer.html

Meta tag maker:
• http://javascript.internet.com/miscellaneous/advanced-meta-tag-generator.html

Mouse tracker:
• http://javascript.internet.com/miscellaneous/mouse-comet.html
• layers mouse tracker: http://javascript.internet.com/miscellaneous/stars.html

MP3 Player:
• http://javascript.internet.com/miscellaneous/mp3-playlist.html