AJAX or Asynchronous JavaScript and XML seems to be all the rage at the moment. Builder has published a handy primer to get started using AJAX today.
AJAX or Asynchronous JavaScript and XML seems to be all the rage at the moment. Builder has published a handy primer to get started using AJAX today.
It is all good and trendy but how the search engines would handle a site written in ajax? I guess they will not handle it at all which makes the technology useful to specific applications only.
Well if you have dynamic sites that rely a lot on POST forms, such as ASP.Net, you may have problems with search engines already. In that case, an URL Rewriting solution would be welcome with or without Ajax.
Regarding Ajax itself, it’s just an old technology that didn’t happen to have a name. Before people would just say Javascript + XML + DHTML, or whatever. But if a nice, consistent framework become the by-product of this sudden hype around it, so be it, at least it will facilitate the communication and sharing of ideas.
The ASP.Net folks are pushing MS hard to include Ajax support on Whidbey, though.
This is just the explanation I needed, simple and to the point. Now at last I can get cracking, er. or is that hacking er. I mean coding er. whatever..
I don’t know. This tutorial didn’t see like a great starting point to me. I’ve been using AJAX for awhile now, and even worked some ajax into osnewsv3, and I thought this tutorial was a little confusing. Check out these:
http://www.adaptivepath.com/publications/essays/archives/000385.php
http://www.xml.com/pub/a/2005/02/09/xml-http-request.html
http://www.ajaxmatters.com/
Basically, this comes down to people wanting to run rich clients in a browser, but nobody wants to run Java so we get this semi-hackish type of stuff.
Something else is going to have to come along because Longhorn will have some sort of rich client in a browser going on via .NET/Avalon, etc…
As far as I understand, there are serious problems not directly adressed by AJAX, such as automatic updates of the data in the client when they change on the server (say, current stock prices). It would be really nice to have a rich client that is optimized for web applications (instead of static pages), but not a specific web application. Something like Java applets without a browser and without the HTML frame…
On closer inspection, the tutorial wasn’t that good, but just the concept of where ajax fits in ie. basically working around the traditional submit is all i needed to know for now, TA for the links..
What browser do I need to see this article?
I have tried Firefox, Opera and IE latest versions but the bottom of the page is cut off.
“Something like Java applets without a browser and without the HTML frame…”
Well, then you’d be referring to rich-client applications…which have existed for quite some time.
What I’d like to see is MS come up w/ an applet-like API for the browser using .NET technologies.
> Well, then you’d be referring to rich-client
> applications…which have existed for quite some time.
Yes they did, but there was not a standard platform for it – something like a “Browser for rich clients”, i.e. a platform to run (portable) rich clients. I think Java Web Start comes closest.
AJAX is best suited to web apps, not web pages if that differentiation makes sense. Anonymoose is partly correct in saying that dynamic pages are already a problem for search engines. Javascript if used to manipulate the DOM is a problem for search engines and accessibility to a far greater degree than most dynamic pages. Search engines cannot parse content generated by Javascript. Some drop down menus etc. But since content is loaded into an iframe by AJAX that content will not be visible to search engines.
So I think AJAX is a good idea for pages that don’t need to be indexed. Backend web application are great for AJAX in my opinion. Obviously Google Mail is another example.
HTML AND Javascript AND buggy browsers are already a mess. I don’t understand the need for more complexity.
Even .NET or Java clients seem to be a better idea than incorporating one more backwards incompatible solution, that needs to be implemented in all browsers, and will probably be buggy even after several revisions.
Unless Microsoft will release Active X for all platforms and all browsers this thing is as useless as a toothache at a Thanksgiving dinner. Just another doomed effort to extend and obfuscate web standards.
You might want to check out XUL. You use XUL with a mozilla browser. Just as you said “a platform to run (portable) rich clients”.
Despite what you may heard, AJAX is a fresh air to rich web apps. But this article definitely misses the point since it directs only to those who use IE and have Active X activated. What about those who chose to use another browser? A decent one?
Anyway, here’s the javascript code for the other browsers, like the Gecko based:
function getHTTPObject()
{
var xmlhttp;
if (!xmlhttp && typeof XMLHttpRequest != ‘undefined’) {
try { xmlhttp = new XMLHttpRequest(); }
catch (e) {xmlhttp = false;}
}
return xmlhttp;
}
jc There’s no need for ActiveX to use this in other browsers. And, actually, in IE you’ll have to look for the appropiate object to load, which may or may not be available.
Mário I just had a look at the article and it says something like:
…
if(window.XMLHttpRequest)
http = new XMLHttpRequest();
else if (window.ActiveXObject)
http = new ActiveXObject(“Microsoft.XMLHTTP”);
…
So I guess it does work on Gecko. The condition they check is different, but it probably works too. They even have a paragraph explaining that bit of code, and another full paragraph about support over most browsers.