[RESOLVED] PHP vs. AJAX

jawa

If I need to chain select boxes together (or dynamically change any of the page content), which way would be better?

AJAX
PHP using iframes

I've not really gotten into AJAX yet, so that isn't really a viable option for me at this time. I'm willing to learn it if needed, but my current way of doing things works fine.

The way I've accomplished this in the past was to reference an iframe inside the HTML (width/height/border = 0, so it's hidden). When whatever condition happens (they choose an option from a select box, they enter a zip code, etc), reload the iframe source using JavaScript (window.frames["iframename"].document.forms["formname"].submit()😉 and pass variables to the iframe PHP using Session variables or setting the variables inside the page, also using JS.

My way works, and works pretty darn snazzy I might add, but is it worth learning AJAX to replace this? Is there another preferred method of dynamically changing content on a page?

If AJAX is the way to go, please back up the response with valid arguments instead of "Use AJAX n00b" or any other such comments.

If anybody would like to see the current code I'm using, I'll post it.

Thanks in advance,
-J

Weedpacket

If you use AJAX, you'll still need something running on the server to handle the requests being made by the Javascript application, so it's still "PHP on the serer, Javascript on the client", and not a "versus" issue.

One issue that I think is relevant is the iframe method has to operate synchronously: make a request, get a response, make a request, get a response.... what happens if two requests are triggered at pretty much the same time, so asecond request is made before the first one has received its response? The <iframe> method can only cope with one response at a time, and the other one gets left behind. Using AJAX, requests and responses can happen asynchronously (that's what the first "A" stands for).

jawa

Good point. I see where using the iframes could be an issue, but in the past I've always used different iframes for different activites, and so far, I haven't had any problems.

For instance, one iframe to deal with chaining select boxes. Another iframe to deal with entering state/zip code info. And another iframe for handling the next dynamic thing on the page, etc.

Let's say I have chained select boxes. The first box has 50 items, and the child box has 50 items for each of the parent items. I choose a value using my mouse, then use my keyboard down arrow to traverse the rest of the box.

Using the AJAX example you provided, Are all of those requests are being sent? Do all of them get processed? If I have a slow connection, do I have to wait for each and every request to get processed and the returned to my browser? Will my browser have to wait on the results from the 1st request before starting the 2nd?

Using my iframe method, only the last item selected would actually return data. Yes, the other items being selected start processing, but if I select another value before the iframe is done reloading from the first selection, the page gets reloaded and new post data gets sent, thereby cutting down processing time. The browser isn't loading & reloading results just because I scrolled through the entire select box.

I guess my question is this: With everything boiled down, is AJAX/PHP significantly better, worse, or the same as iframe/PHP?

-J

MarkR

There are other options:

Don't use a chain of select boxes at all, use normal html links (or radio buttons, or something else). Select boxes are evil for usability because the user can't easily see what all the options are.
Load your entire data set into the client side and do it entirely in client-side JS.

Neither of which would require any ajax or any frames.

However, you may find that the performance is better if you do use Ajax.

You should really use this techique sparingly, particularly if you don't understand it.

IMHO, if you're going to use Ajax in one place, you should use it in many places and have a consistent ajax library and server interface - otherwise you'll end up with a really messy app with lots of small inconsistent ajax RPC entry points.

Mark

cahva

I myself discovered the wonderfull world of ajax a while ago. Im not too fond of javascript but I tested xajax which is PHP class to do the "dirty work" for you. Its very easy to use and I have done CMS and accounting program using it this year. It really speeds up development also!

http://www.xajaxproject.org/

Weedpacket

More comparison can be found at sites like these.

jawa

MarkR wrote:
IMHO, if you're going to use Ajax in one place, you should use it in many places and have a consistent ajax library and server interface - otherwise you'll end up with a really messy app with lots of small inconsistent ajax RPC entry points.

That pretty much gives me my answer. Seeing as I don't have a real good code base to work from for what I need, I'll continue working with what I have.

AJAX seems like the way to go, but it'll just take a bit of time to use it and get familiar with it before charging a client for it. :bemused:

Thanks all...
-J