This article discusses the good and the bad points of
using JavaScript in your website designs. It points out the areas where
JavaScript excels as a web based programming language and also
describes situations where its use can actually detract from the
performance of a website.
First of all, JavaScript is a browser
based programming language that actually runs client side. This means
that any code that you write in JavaScript is delivered along with your
web pages and the scripts that you write actually run from within the
users’ browser rather than directly on the server that is serving the
web page. There are situations where JavaScript is an excellent
solution for implementing neat features in a web design but there are
also situations where using JavaScript can hurt your websites
performance. It is my aim in this article to describe the best ways to
use JavaScript and how to circumnavigate the downsides of using this
versatile and powerful scripting language.
JavaScript for Web Design - The Advantages
JavaScript
is an excellent solution to implement when validating input forms on
the client side. This means that if a user forgets to enter his name in
a form for instance a JavaScript validation function can popup a
message to let him know about the omission. This is a far better
solution that having a server side validation routine handle the error
because the server does not have to do any additional processing. An
asp or php routine could be written to achieve the same task but the
JavaScript would not allow the form to be submitted unless it was
completed properly in the first place, a much more robust solution!
Another
area where JavaScript excels is in the creation of dynamic effects such
as rollover images and scripted slideshows, where its use has become
commonplace. Because JavaScript runs inside the clients browser it can
be used to change the appearance of the users screen after the page has
been sent by the server. This allows it to create some very impressive
dynamic image effects.
JavaScript for Web Design - The Disadvantages
One
of the major draw backs to using JavaScript is that it tends to
severely bloat web pages. JavaScript code can quickly add up to
hundreds of lines of code if you are using it to do anything even
remotely interesting. That said the problem of large chunks of
JavaScript code is easily solved by storing the JavaScript code off
into separate JavaScript source files that have a .js extension. This
cleans up your web page code because the JavaScript code is stored
separately to the HTML page itself, leaving a much cleaner and more
readable web page.
Because of JavaScript’s tendency to bloat web
pages it can be very detrimental to the search engine friendliness of
your web site. This is because when a search engine arrives at your
site looking for quality content and keywords to determine what your
page is al about, the last thing it wants to see is hundreds of lines
of JavaScript code. Again, this problem is easily solves by neatly
storing JavaScript code away in script files with a .js extension and
linking to the script file in your HTML documents.
Conclusion:
JavaScript
is a feature rich and useful browser based script that if used properly
can achieve some great effects and improve the experience for the end
user. There are drawbacks to its use in that it tends to bloat web
pages. The key thing to remember is to get the best of both worlds by
using JavaScript code in external script files. That way the code is
separated from your content so you get all the benefit of JavaScript
functionality but without the adverse effects of the associated code
bloating.