Datasheet

ASP.NET 2.0 AJAX provides the following features (and much more):
❑ AJAX-style communications between client and server. This communication is over web services.
❑ Asynchronous communication. All client-to-server communication in the ASP.NET 2.0 AJAX
framework is asynchronous.
❑ A set of server-side controls that enable rich client-side functionality.
❑ A set of client-side controls and classes that further enable client-side functionality.
❑ A framework for encapsulating client-logic through the creation of namespaces and classes.
❑ Cross browser support. Although there is no official matrix of web browsers that ASP.NET 2.0
AJAX supports, the latest versions of Internet Explorer, Firefox, and Safari are supported. In
addition, Opera is thought to be supported; however, we have not been able to find an official
statement from Microsoft regarding this.
Running ASP.NET AJAX Applications
Unfortunately, not all web browsers ever produced will support ASP.NET AJAX. To run an ASP.NET
AJAX application, a web browser must:
❑ Be relatively modern — ASP.NET AJAX applications are not available in all versions of all web
browsers. Though Internet Explorer version 6 and later, Firefox version 1.5 and later, and Safari
provide support for these applications, older versions may be problematic because of their sup-
port for different versions of the other requirements.
❑ Support the DOM — The capability to update form elements on a page based on new data is
important. Accessing the controls in a standard way means that writing code that runs over a
majority of web browsers is easier than having code that has a large number of
if/then/else
statements that are dependent on the browser version.
❑ Support JavaScript — ASP.NET AJAX requires some amount of actions to occur out on the
client. These actions are done using the JavaScript programming language. Because the major
web browsers support JavaScript, it makes sense for JavaScript to be used for the client-side
programming language.
❑ Possibly have ActiveX enabled on the client — If you are using the Internet Explorer 6 browser
while running on Windows, you may have problems if ActiveX is not enabled.
Who’s Using AJAX?
Great, now that you have seen that there is this technology called AJAX, are you alone in not having
seen or talked about this before? Absolutely not! AJAX has just recently taken off in the second half of
2005 from a mindshare standpoint. As discussions have gone on with counterparts in the development
community, many developers are just now looking to what AJAX can do for their applications and ulti-
mately their customers. So, just who is using AJAX publicly?
❑ Google Suggest — Google Suggest features a dynamic drop-down list box that provides possible
items to search on along with the approximate number of search results.
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Chapter 1: Introduction to ASP.NET AJAX
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