Writing Your First Service in Visual Basic 2008 (part 3)

Making the Service Installable

Currently the service is not in an installable state. We have to add the proper components to allow the .NET Framework to install the service and make it compatible with the Win32 subsystem. In the Solution Explorer, right-click Tutorials.vb and select View Designer.

In the Toolbox, expand the Components section and then drag a ServiceController onto the Tutorials.vb design surface.

After you add the control, you will see it on the designer surface as ServiceController1.

Setting the Service Properties

Right-click ServiceController1 and select Properties. In the properties window, click Service Name and type Tutorials. This name will be listed on the Administrative Tools, Services page. Save the project.

Double-click Tutorials.vb to open the Design window. Right-click anywhere in the gray window and select Add Installer. You should now see the ServiceInstaller1 control.

Right-click ServiceInstaller1 and select Properties. In the Properties window, type Tutorials for the Service Name.

You will see the Description property listed in the Description column of the Control Panel\Services administrator console. You will see the DisplayName property in the Name column of the Control Panel\Services administrator console. You will not see the short name or the service name.

Setting the Startup Options

Right-click the ServiceProcessInstaller1 object and select Properties. For the Account property select LocalSystem.

Additional Configuration Options

To better secure the service, we will set some of the optional security settings available to us in Visual Studio.

Adding a Signature Key File

It is important to protect your application as well as make it safe for others to use. Select Tutorial Properties from the project menu, and then click the Signing tab. Click Sign The Assembly. Select the drop-down box and choose New. Type in Tutorials as the key file.snk name and type in Tutorials for the password.

Adding Security-Specific Settings

After you set up the signature file, click the Security tab. Enable the default security settings by selecting the Enabled ClickOnce Security Settings check box. Save your settings and close the Properties window.

Building, Installing, and Deploying

Now that we have written the code and created installer components that will allow us to use the .NET Framework to install the service, we need to save and build the project.

Select the Save All option. Visual Studio displays the Save Project dialog box. In the Name text box, type Tutorials. Click Save.

You have multiple ways to build the project. You can right-click the project and choose Build. Or you can choose Build from the menu and click Build Solution. You will be able to determine whether your project’s build was successful by looking at the status bar in the bottom left corner of the IDE. If the build failed, review the error list and correct the errors in the build.

After you build the project successfully, it is time to deploy it.

Creating Your Service Storage Location

Open Windows Explorer, and navigate to the Tutorials\Bin\Release directory. Copy the pdb and exe files to c:\temp. If this path does not exist, you can create it, or you can use whatever path you prefer. However, c:\temp is the path I will use in this example. After you copy the files, open the Visual Studio 2008 Command Window by selecting Start, selecting Run, typing cmd at the prompt, and clicking Enter. Type cd c:\temp to switch to the c:\temp directory. Type installutil tutorials.exe to install the service. If this does not work, read the next section to ensure that you have the proper configuration for the installation utilities.

Verifying That You Have .NET 2.0 Installed

At the command prompt you opened in the previous section, type installutil Tutorials.exe. This will run the .NET installutil utility, which will register your service. If you happen to have any other version of the framework installed, the incorrect installutil might be in the current path environment variables. Therefore, when you attempt to register the new service you get an error. You can easily figure out which version of the Framework is installed by typing installutil at the command prompt, and reading the version from the top of the output in the Command Prompt window. At the very top of the output you will see which version of installutil was executed.

If the incorrect version is in the path, your installation will fail. To remedy this, you can either run installutil from the Framework\2.0V directory or you can add the proper path for the 2.0V Framework into your environment variables. After you do this you will need to close the command prompt. When you reopen a new Command Prompt window, you will utilize the proper installutil.

If you do not have the Framework 2.0 installed at all, you can download the different framework versions from the Microsoft Update Web site.

Verifying That Your Service Is Installed

After your service is installed, you can go to the Administrative Tools |Services screen and see the service Tutorials Display Name, with a description of Tutorials. In Windows Vista and Windows XP, click Start, click Control Panel, click Administrative Tools, and then click Services. In Windows Server 2003, click Start, click All Programs, click Administrative Tools, and then click Services.

Right-click the service and select Properties.

<OnStart> Message

Click Start, click Control Panel, click Administrative Tools, and then click Event Viewer.I In the Application log, you should see the EventID 1000 with a Source of Tutorials. Double-click the event and you will see Tutorials Starting. This, of course, is the information we typed in the <OnStart> code.

Now let’s test the rest of the events.

<OnPause> Message

On the Services Control Panel, right-click the service and select Pause. In the Application log, you should see your EventID 1002 event with the <OnPause> message. The actual code does not pause the service.

<OnContinue> Message

After you have validated the <OnPause> event, right-click the service again and choose Resume. You will notice that the only options you have are Stop, Resume, and Restart. At this point you should see your EventID 1003 event with the <OnContinue> message in the Application log.

<OnStop> Message

Click the service and select Stop. The Service Control Manager will call your <OnStop> method. In the event viewer you will see the EventID 1001, which is the Tutorials Stopping event.

This concludes the creation of the first service. Although it is a simple service, it gives you a basic idea of how to create and release a service developed in Visual Basic 2008.