Book excerpt: Ajax and the dynamic double combo

Although Ajax is neither new (debuting in 1998 with Outlook Web Access) nor a technology (in fact, it's a way to use established Web technologies), Ajax programming requires a learning curve surpassing that of a new technology, since it requires as much unlearning as learning. Ajax also attracts different types of IT professionals; there are enterprise developers who want to brush up on improving presentation layers, there are graphic designers and desktop developers aiming to build back-end applications, and there are system admins called on by end users to build nifty UIs.

Ajax in Action by Dave Crane and Eric Pascarello with Darren James, the latest installment of Manning Publication Co.'s In Action series, reaches out to each type of Ajax-ready developer. The book is divided into four parts that provide an overview of why Ajax can be successful, explain the core technologies behind Ajax, describe how to build production-ready software and present five step-by-step projects that use Ajax. Client-side code examples are JavaScript, the underlying language behind Ajax, while server-side code is present in PHP, Java, C#, and Visual Basic .NET.

Chapter 9, "Dynamic double combo," is the first of the chapters that presents a step-by-step development project. The title refers to a double-combination linked list, in which the contents of one selection are dependent on what has been selected in a second list. The project outlined in this chapter enhances simple HTML forms with Ajax by using the data entered in one drop-down list to populate a second list by making a background request to the server. The chapter covers the client-side JavaScript, the server-side Visual Basic .NET and the data exchange format needed for this solution, describes how to refactor the code and make it a reusable component, and shows how to create dynamic select boxes.

Read this sample chapter from Ajax in Action in this PDF.

Learn more about Ajax application security in this Q&A with co-author Eric Pascarello.

Visit the Author Forum for Ajax in Action.

Rate this Tip To rate tips, you must be a member of SearchWinDevelopment.com. Register now to start rating these tips. Log in if you are already a member. Digg This!     StumbleUpon     Del.icio.us    RELATED CONTENT ASP.NET Development How to use jQuery to solve Javascript browser compatibility problems How to write an out-of-browser Silverlight 3 application in 3 steps Silverlight 3 beta SDK download lets developers try new RIA features Visual Studio's IntelliSense for jQuery doesn't autocomplete correctly Dundas Map for .NET kicks up geographic visualization Return to CodePlex: Into the Sandcastle… VBScript Tutorial Use PHP with Visual Studio to create Web sites Visual Studio Team System Add-ins: Conchango Scrum for Team System and Scrum Dashboard Visual Studio 2008 and .NET Framework 3.5 SP1 introduces ADO .NET Entity Designer Chapter Downloads Advanced Windows Debugging Book Chapter and Podcast Book excerpt: Murach's VB 2008 Book excerpt: Building personalized solutions in SharePoint 2007 Book excerpt: Java EE and .NET security interoperability Book excerpt: Building document management solutions in SharePoint 2007 Book excerpt: .NET Framework Design Guidelines Book excerpt: Advanced Windows Debugging Book excerpt: Pragmatic unit testing in C# with NUnit Book Excerpt: Executing activities in Windows Workflow Foundation Book excerpt: Hands-on Windows Communication Foundation ASP.NET and Web Development Book excerpt: Silverlight 1.0 explained Book excerpt: Secure ASP.NET AJAX development Book excerpt: Using the Ajax.NET Pro Library Book excerpt: Introduction to ASP.NET AJAX Controls Book Excerpt: ASP.NET 2.0 Web Parts in Action Is It Always This Easy? Chapter 2 of ASP.NET 2.0 Illustrated Using Validation Controls: Chapter 3 of ASP.NET 2.0 Unleashed Test and debug an ASP.NET app: Chp. 4 of Murach's ASP.NET 2.0 Web Programming with C# 2005 Beginning ASP.NET 2.0: Develop a one-page Web application How to Use Master Pages - Chapter 3 of Murach's ASP.NET 2.0 Upgrader's Guide, VB Edition RELATED RESOURCES 2020software.com, trial software downloads for accounting software, ERP software, CRM software and business software systems Search Bitpipe.com for the latest white papers and business webcasts Whatis.com, the online computer dictionary DISCLAIMER: Our Tips Exchange is a forum for you to share technical advice and expertise with your peers and to learn from other enterprise IT professionals. TechTarget provides the infrastructure to facilitate this sharing of information. However, we cannot guarantee the accuracy or validity of the material submitted. You agree that your use of the Ask The Expert services and your reliance on any questions, answers, information or other materials received through this Web site is at your own risk.