As ASP.NET AJAX continues to grow in both scope and popularity, tutorials and best practices are emerging as well. To help develop new skills or hone existing ones, here we have compiled some recent tips, bits of advice and downloads for working with Microsoft's Ajax technology.
A good starting point is the MSDN article ASP.NET Atlas Powers the AJAX-Style Sites You've Been Waiting For by Matt Gibbs of the ASP.NET team. Gibbs explains the difference in client-server interaction between traditional; Web applications and Ajax-enabled apps. It also covers the ASP.NET AJAX client script library -- which makes it easier for .NET developers to work with JavaScript -- as well client script controls and server controls.
A second MSDN article -- which actually fits into a four-part series on role management in ASP.NET 2.0 apps -- provides a nice synopsis for incorporating Atlas into an existing application. Consultant Peter Kellner writes about two techniques in Microsoft ASP.NET 2.0 Member/Role Management with IIS, Part 3: AJAX Enhancements with Microsoft Atlas:
[C]opy in the Atlas script library, modify your web.config, add the atlas dll to your project and, finally, add some initializing tags in your aspx pages.
The other way to begin working with Atlas…is this. [C]reate a new Web project using the newly installed Atlas template. Next, rename the default.aspx file in case you have your own, then copy in all your existing libraries and pages. Finally, add your sections to the Atlas-enabled web.config file and make sure everything works as before with no Atlas functionality. The final step is to look at the original default.aspx file and copy the Atlas constructs into the headers of an existing page to which you want to add AJAX capabilities.
Once you understand the basics, it's time to take the technology for a test drive. ASP.NET AJAX is available as a free download, and there's also an ASP.NET AJAX Control Toolkit, which offers a variety of ready-made controls and components, from cascading drop-down menus and collapsible panels to TextBox watermarks and rounded corners. In addition, there are controls and templates for writing your own Atlas extenders.
The ASP.NET AJAX Control Toolkit currently contains more than 20 components. Microsoft aims to continue updating it regularly, with its own work as well as that of outside developers, but odds are it will represent just the tip of the iceberg when it comes to Web application functionality. Thus bloggers are beginning to post their own Atlas add-ins.
Over on the Code Project, Ahmed Saeed has posted code for an ASP.NET DropDownList that includes shape names and an image control. Select the shape name "circle" and a circle will appear. Read about this application here.
A second sample comes from Shiju Varghese, who writes about and provides sample code for drag and drop controls as well as opacity, fading and time limits in animation, which comes from the AtlasUIGlitz JavaScript library. Check out Varghese's blog entry here.
There is also the Focus extender, which allows developers to set the input focus to a particular control on a Web form. It was written by Chris Crowe and can be seen here.
