ASP.NET 4

In its latest version, ASP.NET continues to plug in new enhancements and refinements. The most
significant ones include:
Consistent XHTML rendering; ASP.NET 3.5 made it possible to render ASP.NET web pages as
XHTML documents, but there were still a few issues to trip up unsuspecting developers. (For
example, you had to opt-in through a configuration file setting to get true, strict XHTML.) ASP.NET 4
smooths out the wrinkles and makes clean, quirk-free XHTML the standard. Chapter 3 covers the
details.
Updated browser detection: ASP.NET 4 ships with updated browser definition files, which means its
server-side rendering engine can recognize and provide properly targeted support to a wider range
of browsers. Better-supported browsers include Google Chrome, Internet Explorer 8, Firefox 3.5,
Opera 10, Safari 4, and the mobile browsers for the BlackBerry, IPhone, IPod, and Windows Mobile
operating system. You’ll learn more about browser definitions in Chapter 27.
Session state compression: Microsoft added the System.IO.Compression namespace with gzip
support in .NET 2.0. Now, ASP.NET can use it to compress the data it passes to an out-of-processs
session state service. This technique makes sense in a fairly narrow set of circumstances, but if it
applies to you, the performance improvement is almost automatic. Chapter 6 explains how it works.
Opt-in view state. Rather than disabling view state selectively, per control, you can now turn it off
for an entire page and then opt-in when necessary. This allows you to easily slim down your page
size. Chapter 6 shows you how to use this feature.
Extensible caching: Caching is one of ASP.NET’s premiere features, but with the exception of SQL
Server cache dependencies, caching hasn’t seen any new features since .NET 1.0. With ASP.NET 4,
Microsoft finally begins exposing the caching extensibility points that will allow them (and other
developers) to use new types of cache storage, including distributed caching solutions such as
Windows Server AppFabric and memcached. Although these extra bits of infrastructure aren’t all
there yet, Chapter 11 shows how the model works.
The Chart control: For years, ASP.NET developers have been forced to master the GDI+ drawing
model or purchase a third-party control to create a respectable graph. Now, ASP.NET includes an
impressive Chart control that supports a range of beautifuly rendered two- and three-dimensional
graphs (including line, bar, curve, area, pie, doughnut, and point charts, complete with features like
error bars and Bollinger bands). You’ll explore the Chart control in Chapter 28.

Revamped Visual Studio: Although the Visual Studio 2010 interface still follows the same basic
design, it’s been completely rebuilt using .NET and WPF (Windows Presentation Foundation). Along
the way, Microsoft managed to introduce a few frills, like the enhanced IntelliSense you’ll learn
about in Chapter 2, and the new visual designer that makes designing Silverlight content a breeze
(Chapter 34).
Routing: ASP.NET MVC includes support for meaningful, search-engine-friendly URLs. In ASP.NET
4, you can use the same routing technology to redirect web form requests. Chapter 17 demonstrates
this technique.
Better deployment tools: Visual Studio now allows you to create web packages, compressed files
that contain your application content and other details such as SQL Server database schemas and
IIS settings. Web packages also work in conjunction with a new web.config transformation feature
that allows you to cleanly separate the settings that apply to the test build of your application and
the ones that apply to the deployed instance. Finally, you can load and precompile a newly
deployed application more easily with the IIS application warm-up module. Chapter 18 has the
details on all these features.
Although these features are undeniably useful, the most impressive new additions to ASP.NET
development come from two separate add-ins: ASP.NET MVC and ASP.NET Dynamic Data. Both of
these features invite you to abandon part of the traditional ASP.NET development model for a different
approach, with a different set of benefits and drawbacks. In many ways, they represent the start of a new
direction in web application programming. But if either one fits your needs, it has the potential to
reduce your work dramatically.