Datasheet
(IL), which is a just-in-time (JIT) compilation at runtime. This means that the IL is changed into machine
language that the current operating system can understand and run. This concept enables you to develop
software in virtually any language that compiles to IL. Microsoft provides several languages, such as C#,
Visual Basic .NET, and managed C++.
Another main pillar of the .NET Framework is the Base Class Library (BCL). The BCL is an extremely
large and rich set of classes that provide out-of-the-box functionality for developers. This includes
classes for string and XML manipulation, ADO.NET classes for database interaction and structured data
operations, and much more.
The .NET Framework 3.0
The .NET Framework 3.0 is a next-generation development platform that is available out of the box on
Windows Vista and can also be downloaded for other versions of Windows, including Windows XP SP2
and Windows 2003 Server. Essentially, the .NET Framework 3.0 is an extension of .NET that provides
developers with a library of managed APIs. The .NET Framework 3.0 components are as follows:
❑ Windows Presentation Foundation (WPF; formerly known as
Avalon
)
❑ Windows Communication Foundation (WCF; formerly known as
Indigo
)
❑ Windows CardSpace (WCS; formerly known as
InfoCard
)
❑ Windows Workflow Foundation (WF; formerly known as
WinOE
)
Figure 1-4 illustrates the .NET Framework 3.0 architecture.
Figure 1-4
Windows Presentation Foundation
Windows Presentation Foundation (WPF), formerly known as Avalon, provides a framework for devel-
oping a rich user interface experience. Unlike Windows Forms, which is driven by code, WPF can be
developed with a declarative markup model. This markup is called
XAML
(pronounced
zamel
), which
stands for
Extensible Application Markup Language.
XAML is XML based, which means that all you need to develop a user interface layout is your handy
Notepad executable. Check out the following code listing for a simple example:
WPF WCF WCS
.NET 3.0
.NET 2.0 (BCL, CLR, ASP.NET, etc.)
Windows
Visual Studio
WF
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Chapter 1: An Introduction to Workflow and Windows Workflow Foundation
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