Using External JavaScript Files

When you have lots of JavaScript functions and you plan to use
them on many web pages, it is always advisable to keep them in a
separate file, and then include that file on every page where
those functions are required. This way, you can better organize
them, you don't have to copy/paste the code again and again
(imagine if it runs to 100 or more lines!!), and you'll be forced
to write more generalized code for better integration and
scalability.

Besides, enclosing the common JavaScript routines in external
files keeps your web pages uncluttered and search engine spiders
and crawlers are able to reach the important content easily. They
don't have to shuffle through tens of lines of scripts.

In the first edition [that appeared in my newsletter - BYTESWORTH
REACHOUT] of my article I had omitted the process of creating the
external JavaScript files, but when one of my readers asked me
how to do it, I had to re-write the article.

It's very simple. Use any text editor of your liking (if you
hand-code your HTML, you can use the same editor that you use for
your HTML editing). Write the required code, and save the file
with .js (dot js) extension.

I'm going to give you a small example.

Suppose your JavaScript file is "myjfuncs.js".

and it has a function to return the bigger number of the two
supplied as parameters (you can simply start with the function,
no need to write

So when we use one of its functions in a JavaScript:



In this way, we can use all the complex functions contained in
the myjfuncs.js file.