Ajax--The confusing guide, part 1th: An overview of AJAX tools and technologies

Ajax (asynchronous JavaScript + XML) programming technology is gradually leading the field of WEB application development. Every day new developers enter the halls of Ajax development, and they have different development backgrounds. The 1th part of this series will provide an Ajax development resource memo from the Ibm®ajax developer Expert Group. The authors provide you with useful information based on their own ramp-up experience, which can help you quickly get into the orbit of efficient Ajax development.

Ajax is a WEB application client technology that combines JavaScript, cascading style sheets (cascading style sheets,css), HTML, XMLHttpRequest objects, and Document object models Model,dom), for more information on the various standards, see resources. An Ajax application running on a browser communicates with the WEB server in an asynchronous fashion and updates only part of the page. By leveraging Ajax technology, you can provide a rich, browser-based user experience.

Before you start the Ajax journey, you need to be familiar with many different languages, standards, tools, and libraries. It may be a bit reluctant to choose between different options and assemble a development environment at the outset. The authors will help you avoid some of the more common and annoying problems you may encounter during your trip, based on their own ramp-up (preparation for the initial phase of the project).

Embark on an Ajax journey

Ajax will change the user experience on the site, the previous click-Show page experience will become interactive, flexible desktop application experience. Users can avoid page reloading and avoid waiting for the next part of the content to be rendered. You may be thinking, it all sounds good, but how can you do it? To answer this question, let's look at some behind-the-scenes stories behind Ajax technology.

Ajax is a collection of WEB technologies and standards that allow you to use the client's machine to run an important part of the application logic behind it, not just to render the application's output:

Hypertext Markup Language (hypertext Markup language,html): Defines what is ultimately presented to the user.

Cascading style sheet (cascading style sheets,css): Defines the style (or decoration) of the rendered content.

Document Object Model (Doc object model,dom): An API that browsers use to expose content to JavaScript scripts. The script can then use the DOM to dynamically modify the content before the user sees the content.

XMLHttpRequest object: Facilitates interaction between browsers and servers and is invoked through JavaScript scripting.

JavaScript: A programming language that is executed in a browser that is bonded to all other Ajax components. Scripts can listen for events that occur in the browser, such as clicking a button, and use XMLHttpRequests to callback the server to react to events, and then modify the DOM tree based on the results returned.

All of these technologies are executed in the user's Web browser, and the user's Web browser acts as a platform for executing Ajax programs.

If you want to use Ajax, it's worth noting that the technology that makes up it is standards-based, but browser-specific. In other words, the same application may behave differently on different browsers. However, as an application creator, you need to understand the differences between different browsers, since it is not possible to limit the user's use of a particular browser or to ignore the fact that the client's browser may not support CSS or DOM.

To become an efficient Ajax developer, you need to:

Understand the technology that forms the basis of Ajax development.

Understand the available runtime platforms and Web browsers.

The IDE that supports various languages is used when developing Ajax applications.

has debugger and application testing tools for a variety of environments and languages.