Form/dropdowns that calculate total into a textarea?

Howdy,

I've got a form with many dropdown boxes - what needs to happen is people select things in the dropdown boxes and a number is calculated at the bottom. Each dropdown box might have something like:

Type of user: * Newbie (1 point)
* Regular (5 points)
* Addict (10 points)

Donation: * $0-$5 (add 10 points)
* $5-$10 (add 20 points)
* $10-$20 (add 25 points)

Time on forum: * 1 week (multiply by 1)
* 1 month (multiply by 2)
* 6 months (multiply by 3)
* 1 year (multiply by 4)

At the bottom of the form there is a "Calculate" button, and a textarea called "total points". What I want to happen is for a number to be calculated when they click on the button, depending on what was chosen in the dropdown box - and the total value comes up in the textarea.

(If it's possible, the button doesn't even need to be there - maybe anytime something is selected in the dropdown box, the total is automatically calculated?)

I'm not sure how I calculate this, or give each dropdown box entry its own value. I realize I can do this in PHP, but it's important that it all happens on the one page.

Thanks!

You can find examples of math operators here (http://www.paschools.pa.sk.ca/javascript/math.htm).

.....Willy

Put the corresponding point in the option value so that you'll know how many points is associated to an option.

<select name="userType" onchange="calculate()">
<option value="1">Newbie</option>
<option value="5">Regular</option>
<option value="10">Addict</option>
</select>

And use onchange event handler to do the calculation.
Try to do the code on your own and post back here if you encountered any problem.

Don't forget to check your other thread (http://www.webxpertz.net/forums/showthread.php3?s=&threadid=27584) for replies.

.....Willy