Displaying Dynamic Text on A page

John_Cross

hi
What I want to do is have a php page that has a form. When a person comes and selects the values on the form i want the total amount of the selected values to appear on the screen as they are selected.
ie on a pulldown we have the values 1, 3, 6, 7
on another we have 5, 7, 3, 1
if the user selected 6 in the first and 3 in the second i would want 9 to appear at the bottom of the page. Can this be done and can you show me how 😉 thx

sarahk

What you need is client side processing (php is serverside) so here's some javascript to get you started.

<script language="Javascript">
function addIt()
{
  var fldTotal = document.MyForm.Total;
  var newVal = parseInt(document.MyForm.firstVal.selectedIndex);
  newVal += parseInt(document.MyForm.secondVal.selectedIndex);
  fldTotal.value = newVal;
}
</script>
<FORM NAME="MyForm">
<select name="firstVal" onChange="addIt()"><option value="0" selected>0</option><option value="1">1</option><option value="2">2</option><option value="3">3</option></select><br>
<select name="secondVal" onChange="addIt()"><option value="0" selected>0</option><option value="1">1</option><option value="2">2</option><option value="3">3</option></select><br>
<input type="text" name="Total">
</FORM>

John_Cross

so i should use javascript instead now i see 🙂 thx

mrmufin

Originally posted by sarahk
What you need is client side processing (php is serverside) so here's some javascript to get you started.

That's just dandy except for the fact that nothing will work as soon as someone tries to use it on a browser where JavaScript is disabled...

sarahk

I guess that just means you have to look at your target market. If there is a risk of that then you will need extended coding.

I'm probably blinkered by because my target groups are not IT gurus, they have been using the internet for < 5 years, they upgrade their browsers when their ISP tells them to - therefore their browsers are capable of javascript and they wouldn't know how to turn it off.

For a great user experience I believe you need a mix of both client and serverside. I do think the javascript sites put too much emphasis on client side processing - some things are clearly better done behind the scenes.

mrmufin

Originally posted by sarahk
I'm probably blinkered by because my target groups are not IT gurus, they have been using the internet for < 5 years, they upgrade their browsers when their ISP tells them to - therefore their browsers are capable of javascript and they wouldn't know how to turn it off.

The first general assumption that I make in designing every application is that if something can be disabled on a client web browser, it will be disabled on the client web browser.

The second closely related assumption that I make is that the person sitting in front of that web browser has all the 'internet savvy' of my mother. I've been to far too many sites which tell me that 'You must have cookies enabled on your web browser'... I can't help but picture my mother, upon being confronted with a message like that, running to the kitchen and getting a box of Oreos and setting it on top of the computer then wondering why the site still doesn't work on her computer.

While JavaScript is fine for cute, fluffy, fuzzy bells and whistles and other such frivolous gizmos, it should never be relied upon to do anything important (like actually performing a form submission, or be the sole tool for data validation) if, for no other reason, than the fact that it can be disabled on most browsers.

Back in the old days (around 1997 or so) there used to be a <script></noscript> tag set and its usage was encouraged for folks designing JavaScript-intensive websites, to assure that the page 'still worked' on browsers where JavaScript was either turned off or (not yet, at that time) available. Funny how that tag set seems to have vanished from the web design toolkit...

Perhaps if there were highly reliable methods of determining whether or not JavaScript was available and enabled on a client browser, along with a single, commonly-deployed version of JavaScript, I'd consider resuming my short-lived love affair with it. But JavaScript functionalities differ intensely across browser version and OS, and I have not the time, desire or resources to assure that my script will function reliably on all browsers. Nor do I expect other web designers and application developers to test their stuff on the relatively 'oddball' combonitaion of OS and browser that I prefer. (Which, incidentally is Opera 6.02 on SuSE 7.3 Linux.)

I've been to far too many sites, waited for eons (okay, a good 30 seconds, anyway) for a page to load only to have nothing be displayed on the screen of my Netscape 4.78 web browser on Linux. After a quick stroll through the client-side code, it's revealed that some bozo web designer who wouldn't know a Solaris server from a fried egg decided to do some fancy JavaScript user-agent parsing inside of an if/else statement and decided that my browser simply 'can not exist', so it wasn't granted the privelege of a document.write() function.

I have absolutely no expectations that web designers should or will stop using JavaScript. Nor do I expect them test their scripts on every browser version on every OS. That's not practical today, and it's certainly not getting any more practical. But I have every expectation that decent web designers will not rely on JavaScript, Cookies, Java, Flash, RealMedia, Wind-blows Media Player, or any other optional client-side functionality to be present in order for their site to work.

Just my too sense... Have a nice day!

siwis

Nice sentiments mrmufin! Couldn't agree more. Sites these days are a mixture of over complex "I'll do it because I can" type coding and download this plug-in types. I'd sooner go elsewhere than have any additional baggage chucked onto my machine.

sarahk

Just to add a belated additional comment. There are times when javascript is essential and if you look at the w3 schools site you can easily limit yourself to pretty generic scripting - and yes, you may have to accept a few losses but I know from my checking the logs that I could count them on one hand and we get our share of traffic.

Yes, cookies are a waste of time. I doubt many small sites have the need to truly personalise their sites and the user experience using cookies, a database will do! However I do appreciate not having to login here each time I return!

Your comments about the boy racer elements in code - the snowflakes falling, the orbs following the mouse, flash and music are spot on. But the kids have to learn to code somehow and lets let them play before subjecting them to the "real world".