Dissecting ASP.NET Version 3.5's Web.config File
In November, Microsoft released the final version of ASP.NET 3.5 and Visual Studio 2008. As discussed in An Overview of ASP.NET 3.5 and Visual Studio 2008, version 3.5 is not a major reworking of the .NET Framework. Rather, it adds new classes and functionality on top of the existing core.
If you've had a chance to check out Visual Studio 2008, you may have noticed that it creates a rather verbose Web.config file with a bevy of configuration elements not found in the more terse Web.config file created by Visual Studio 2005. Likewise, when opening an existing Visual Studio 2005 project in Visual Studio 2008, you are prompted with a dialog box asking if you want to upgrade the website to use .NET Framework version 3.5. If you click Yes, Visual Studio updates the application's Web.config file to include the additional markup.
In this article we will examine each of the additional configuration elements added by Visual Studio 2008 to ASP.NET 3.5 applications.