Adding Ajax

Chapter 6. Dynamic Data

Ajax has had a significant impact on traditional web approaches to data retrieval and updates. You realize this the first time you edit information on a web page "in-place" or delete a row of data without the page reloading. Implementing dynamic data updates and queries through Ajax can have the greatest positive impact on your web applications.

Among the different categories of Ajax-enabled dynamic data effects are:

• In-place editing

• Instant reflection of new or newly updated data

• Autocompletion in text fields

• Context-specific selection lists

• Immediate removal of deleted data

The data update effects such as in-place editing and instant deletions are also easy to manage when scripting is disabled, just by providing links to forms for doing more traditional updates. These links can be added in NOSCRIPT elements, but a better approach is to provide these nonscripting solutions as an option for every user, script-enabled or not. Providing more than one way to update data is actually seen as a customer service, so in this instance, Ajax and accessibility go hand in hand.

In addition to data updates, Ajax can also be used to enhance data querying and display through the use of autocompletion of search terms or by providing the ability to sort data using drag-and-drop functionality. Visual effects can be used to specifically highlight certain aspects of the data, though you have to be careful to ensure that important information doesn't depend solely on a visual effect. ...