How to Convert an Existing ASP.Net Application to ASP.Net AJAX application?

To convert an existing ASP.Net application to ASP.Net AJAX application, we need to configure some new elements to the web.config file.

The following are the new elements that should be added to the existing web.config file,

•  The <configSections> element
• The <controls> element
• The <assemblies> element
• The <httpHandlers> element
• The <httpModules> element
• The <system.web.extensions> element
• The <system.webserver> element
• The <configSections> Element

Refer the following link to know more about these elements.

Configuring Existing ASP.Net Application with ASP.Net AJAX

When we install ASP.Net AJAX framework, it installs System.Web.Extensions assembly to GAC.

And, when we choose to create ASP.Net AJAX enabled Website from the project template of visual studio, it creates the Web.Config file with necessary settings for ASP.Net AJAX framework.