1. JavaScript Big fun with JavaScript in the real world
Very early in the morning
February 17, 2000

2. Why JavaScript? You can’t deal with a Java applet
You want more glitz on your pages
You need some active widgets that HTML does not have
You want on-the-fly calculations
User’s need the option to do database lookups without submitting the HTML form they are filling out

3. Why NOT JavaScript?
Some users have turned off JavaScript in their browser
Semi-broken implementations
Some browsers will never support it
You might have to special case the code depending on which browser the user has…
With JavaScript, you are signing up for more maintenance and testing costs

4. The basics JavaScript lives in the HTML page surrounded by the tags
<script language="Javascript">
<!-- hide this from lame browsers
Your code goes here
// -->
</script>
You get variables, some event handling, and the chance to open new windows without a trip back to the web server

5. Debugging alert("some string") is about as good as it gets
Do yourself a favor and edit the HTML page locally so you are not uploading it to the web server each time you change something while debugging
Typing javascript: into the location in Netscape gets you a console

6. Example: Glitz Event handlers let you animate things
<a href="/foo" onMouseOver="funct()" onMouseOut="funct2()"<a>
OnClick, OnLoad, OnSubmit, etc. let you attach functions to elements of a page
You can change element of the page from the event handler function

7. ...Example: Glitz
Javascript functions can stuff values into fields, open windows, or change the images
Elements on a page can be addressed like this: document.forms[0].elements.foo.value
See

8. Example: Calculations
Running totals are a natural addition to many sorts of forms
Unfortunately, JavaScript’s floating point number support is less than optimal
See the wretched JAWS timesheet
See the well-loved FormsNirvana POT

9. Example: DataBase lookups
Nobody can remember all the job titles or department names at the University
You might want to spawn a child window to do a lookup and auto-fill an HTML form field.
Example: the conflict of interest form at

10. Summary
Do not require the use of JavaScript. Give the JavaScript-challenged equal access to your site
Debug carefully. Alert() is your friend.
Test on multiple platforms (various browser versions on Unix, Mac, & PC)
JavaScript is not harmful when used under controlled conditions