California Ajax Solutions Team

www.CalAST.com

This page briefly describes JavaScript, the client side programming language used in most Ajax applications. JavaScript usually runs as part of the web browser, allow it can be used in CGI scripting. The JavaScript code is generally downloaded from the web server, either as part of a web page or as a separate library included by a web page.

Despite its name, JavaScript shares little with the programming language Java other than a general C-like syntax, including a number of reserved words. JavaScript, as its name implies, is a scripting language, and can be used to implement fairly linear code. This is quite different from the enforced object-orientation of Java. However, JavaScript can be written in an object-oriented fashion using prototypes instead of the class syntax found in languages like Java or C++ - or even PHP.

JavaScript is a key component of most interactive web sites. By this, we mean web sites that are dynamic and function more like applications. In contrast, a static web site is simply designed for viewing, possibly with some navigation capabilities (like a DVD) and simple activity like form submission. If you want to design a web site that the user will work with after it has been downloaded from a server and without additional downloads, then JavaScript code running on the client machine provides this capability.

We won 't address the specific characteristics of the language, as that topic is well covered in many books and web resources. The sidebar illustrates some differences.

Instead, we will provide any articles we create that might be of interest to JavaScript programmers and web designers. Since we are strong believers in object-oriented programming, this will tend to be the focus of our writing - but there are other "gotchas" we encounter in designing cross-browser applications, and we will try to address those as well.

This article is a good place to start in that it demonstrates how we create an object for reuse in a number of different sites.

Presenting database query results in web pages
 

JavaScript is not Java

JavaScript Java
weakly typed strongly typed
prototypes classes
usually works within browsers usually stand alone programs
objects are associative arrays objects are typed
functions are objects functions are not objects
mostly used in writing scripts designed for writing programs