Site development

GnomeSharpie

I am wanting to create a online form that would change depending on the users input.
For examle.
Say if a user has the following selections from a drop down box.

car
truck
suv

If the user picks car I would like a drop down menu to apper and have the following selections..

2 door
4 door

You get my drift....
Also, I would like to have a field where a user could enter names in like a spreed sheet format. The user could enter as many names as they wanted the form would just keep growing. Once the user is finished all the user selected info needs to be processed by php and dumped into a database. I can handle the php and database stuff it's just getting the form to dynamically modifiy itself on the fly is what I'm not sure about.

TIA

bart

As PHP is a server side script, you will need to use a client side script to dynamically update the form on the fly. Javascript is what you need. I can't really help with the javascript code though I'm afraid.

winterbeef

Try this:

<html>
<head>
<script language="javascript">
<!--
var cities = new Array();
cities['ny'] = new Array('Albany','Syracuse','New York City');
cities['nj'] = new Array('Trenton','Elizabeth','Roselle Park');

function repop(d,s) {
var state = s.options[s.selectedIndex].value;
var cityarray = cities[state];

for(var idx=0; idx < cityarray.length; idx++ ) {
	tmp = new Option( cityarray[idx], cityarray[idx] );
	d.options[idx] = tmp;
}
return true;

}
// -->
</script>
</head>
<body>
<form>
<select name="state" onChange="repop(this.form.city,this)">
<option value="ny">New York</option>
<option value="nj">New Jersey</option>
</select>
<select name="city">
<option value="">Select a State...</option>
</select>
</form>
</body>

HTH

MrAlaska

As you can probably tell from the code Winterbeef posted, building a dynamic form can get complex because you need to load ALL the data that might get included onto the client. Of course, the client also needs to have javascript turned on.

I had to turn javascript on in my browser when the form wouldn't work on this site after my laptop broke down. It is a spiffy little javascript form, though, check out the source and you will see a lot of information that was loaded no matter what you clicked.

http://www.csd.toshiba.com/cgi-bin/tais/su/su_sc_modSel.jsp

winterbeef

Originally posted by MrAlaska
....
course, the client also needs to have javascript turned on.
...
lot of information that was loaded no matter what you clicked.
....
[/B]

True & true!

As for JS being turned on, I know it is a hotly-debated topic that I'll remain silent about...

One benefit of doing it in JS is responsiveness -- after the initial page loads (which could be huge if your JS arrays are huge), the repopulation of the SELECTs happens <kinda>instantaneously</kinda>. No need to go back to the server.

in my opinion/experience, you'd need a lot of data in the JS to notice a slowdown in the initial page loading time. You might disagree.

Oh, slight tangent, something that gets fun is using PHP to write JS -- say you passed a $country in to the page somehow, you might draw different JS arrays for state[] & city[].... Fun!

GnomeSharpie

Thanks guys for all your help. You have got me on my way. Now what about embedding a spread sheet where a user could enter an infinite set of data. For example: Entering more than one name and still keeping each name as a seperate record. Maybe I need to be looking at Java for something like this?

TIA

Gnome

MrAlaska

Originally posted by GnomeSharpie
Maybe I need to be looking at Java for something like this?

Java might be a bit heavy for this one, but it could work.

An infinite set of entries presents some challenging issues whether you deploy a server or client side solution.

It would be easier if the user could enter how many entries they wished to make, then let PHP build the page based on that.

You could have either Java or javascript keep popping up a new input box until the form is submitted, which would give you a reliable method of ensuring proper data entry.

You could have PHP build a LOT of input fields (not elegant at all), or one big textarea then parse the names on the back end.

To me the textarea seems the best solution, then split it on the back end for one entry per new line. You could have javascript expand the textarea as the list grew if you wanted (not really necessary), but the form would work whether javascript was enabled or not. It would depend on the users being smart enough to put each name on its own line, though, and trusting users to enter data properly is problematic at best.

[EDIT] Upon further thought, a javascript solution would probably be best in this case. Your page is already javascript dependant, anyway, and a javascript dialog box would be the most elegant way to keep asking for more input and provide a button for when they are through. Plus, it would help validate the data.[/EDIT]