Learning WCF

ServiceHost

Regardless of the hosting environment, the service model provides a consistent runtime experience for host initialization, operation calls, and message processing. The ServiceHost type, part of the System.ServiceModel namespace, is the centerpiece of this hosting story. All WCF services must be associated with a ServiceHost instance to be accessible at runtime. Figure 4-1 illustrates the allocation of ServiceHost and associated service types for Windows service and IIS hosting.

Figure 4-1. Each ServiceHost is always associated with a particular service type

Each ServiceHost instance is initialized with information about the service type, one or more service endpoints, optional base addresses, and behaviors that govern how the service model processes requests to the service. In this section, I’ll explain the mechanics of the ServiceHost.

Initializing the ServiceHost

Example 4-1 illustrates a simple example of a console host application initializing the ServiceHost programmatically. In fact, this is the entire listing for the host application. When the application is launched, the ServiceHost is constructed with the service type, HelloIndigo.HelloIndigoService. A single endpoint is created, exposing its operations from the HelloIndigo.IHelloIndigoService service contract over NetTcpBinding. Recall from the introduction to these concepts in Chapter 1 that when a complete URI ...