Datasheet

<Window x:Class=”XamlSample.Window1”

xmlns=http://schemas.microsoft.com/winfx/2006/xaml/presentation

xmlns:x=”http://schemas.microsoft.com/winfx/2006/xaml” Title=”XAML Sample”

Height=”150” Width=”200”>

<Button Width=”100” Height=”50”>I am a button!</Button>

</DockPanel>

</Window>

This creates a form that looks like Figure 1-5.

Figure 1-5

Although WPF and XAML are separate Windows Workflow Foundation components, XAML plays a

role in the declarative model of workflow development (which you learn more about in later chapters).

Windows Communication Foundation

Windows Communication Foundation (WCF), formerly known as Indigo, is a framework on which you

can create SOAs based on industry standards.

SOA is a buzzword of recent years that can cause a lot of controversy when people of the technical per-

suasion get together to discuss it. Essentially, SOA describes an architecture of loosely coupled services

(usually web services) that expose a unique and discrete functionality. Usually, these services perform

one very small task, but they perform it well.

Building an SOA at an enterprise is a lot different from building a singular application. SOA provides the

foundation to build applications — it is not an application itself. Imagine a company that manufacturers

and sells widgets at retail outlets. The organization might have services to submit a bill of materials, to

order new widget glue, or to receive and process purchase orders.

Now back to Windows Communication Foundation. One of the biggest advantages of WCF is that it

provides a unified platform on which you can develop distributed applications. In the past, if you

wanted to develop a distributed application on the Microsoft platform, your options included ASP.NET

Web Services (ASMX), .NET Remoting, Enterprise Services, WSE, and MSMQ, to name a few. That’s a

daunting list, isn’t it?

WCF uses industry standards such as SOAP to bring all these technologies together. This enables appli-

cations built on the Microsoft stack to interact with technologies from other vendors, such as Java.

Essentially, WCF is the replacement and glue for these technologies of yesteryear.

Chapter 14 discusses SOA and WCF in greater detail.

Chapter 1: An Introduction to Workflow and Windows Workflow Foundation

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