C# 4 and .NET 4

684 ❘ ChaPTer 25 windOws services
When you double-click QuoteService, you get the
Properties dialog box shown in Figure 25-12. This dialog
box enables you to view the service name, the description,
the path to the executable, the startup type, and the
status. The service is currently started. The account for
the service process can be changed with the Log On tab in
this dialog box.
net.exe utility
The Services snap-in is easy to use, but the system
administrator cannot automate it because it is not usable
within an administrative script. Controlling services with
a tool that can be automated with a script, you can use the
command-line utility net.exe. The net start command
shows all running services, net start servicename
starts a service, and net stop servicename sends a stop
request to the service. It is also possible to pause and to
continue a service with net pause and net continue
(only if the service allows it, of course).
sc.exe utility
Another little-known utility delivered as part of the operating system is sc.exe. This is a great tool to play
with services. Much more can be done with sc.exe than with the net.exe utility. With sc.exe, you can
check the actual status of a service, or configure, remove, and add services. This tool also facilitates the
deinstallation of the service, if it fails to function correctly.
Visual studio server explorer
You can also control services using the Server Explorer within Visual Studio by selecting Services. The
Services item is listed in the tree view with the first element Servers; below that you can find the name of
your computer, and below that there’s the Services item. By selecting a service and opening the context
menu, you can start or stop a service. This context menu can also be used to add a ServiceController
class to the project.
To control a specific service in your application, drag and drop a service from the Server Explorer to the
Designer: a ServiceController instance is added to the application. The properties of this object are
automatically set to access the selected service, and the assembly
System.ServiceProcess is referenced. You can use this instance to
control a service in the same way you can with the application that you
develop in the next section.
Writing a Custom service Controller
figure 25-12
In this section, you create a small Windows application that uses the
ServiceController class to monitor and control Windows Services.
Create a WPF application with a user interface as shown in
Figure 25-13. The main window of this application has a list box to
show all services, four text boxes to display the display name, status,
type, and name of the service, and six buttons. Four buttons are used
to send control events, one button for a refresh of the list, and one
button to exit the application. figure 25-13
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