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