How to determine if starting inside a windows service?

Question

Currently I'm checking it in the following way:

if (Environment.UserInteractive)
    Application.Run(new ServiceControllerForm(service));
else
    ServiceBase.Run(windowsService);

It helps debugging a little and service can also be run using the executable. But assume now that the service requires interaction with the user desktop so that I have to enable "Allow service to interact with desktop" in the properties. This of course breaks this way of checking. Is there another way?

Answer 1

It's not perfect, but you could probably do something like this:

public static bool IsService()
{
    ServiceController sc = new ServiceController("MyApplication");
    return sc.Status == ServiceControllerStatus.StartPending;
}

The idea is that if you run this while your service is still starting up then it will always be in the pending state. If the service isn't installed at all then the method will always return false. It will only fail in the very unlikely corner case that the service is starting and somebody is trying to start it as an application at the same time.

I don't love this answer but I think it is probably the best you can do. Realistically it's not a very good idea to allow the same application to run in either service or application mode - in the long run it will be easier if you abstract all of the common functionality into a class library and just create a separate service app. But if for some reason you really really need to have your cake and eat it too, you could probably combine the IsService method above with Environment.UserInteractive to get the correct answer almost all of the time.

Answer 2

Why not just use a command line switch?

// Note that you have to add the params argument, 
// which isn't usually present in windows services
private static void Main(params string[] parameters)
{
    ....

    if (parameters.Length > 0)
    {
        if (parameters[0].ToLower() == "/console")
        {
            Application.Run(new ServiceControllerForm(service));  
        {
        else
        {
            ServiceBase.Run(windowsService);
        }
    }
}

Answer 3

Instead of using the Environment.UserInteractive property, modify the startup method of your service to check for a "-console" command line argument. If the argument is present, then run as an ordinary application. If not, run as a service. It's not as automated as the property check, but it'd be easy to add a shortcut to the desktop that adds the "-console" command line argument for you.

As an aside, you need to be aware that interaction with the desktop has been disabled in Windows Vista and beyond. If you are running a Windows service that needs to interact with the user, the approved way of doing this now is to separate your front-end application from your Windows service and have them communicate using something like WCF.

If you need to debug your Windows service (whether it's running as a service or as an application), put a call to System.Diagnostics.Debugging.Break() in your startup method. This will force a prompt that allows you to enter a debugging session. I use this technique to debug my Windows service all the time.

Answer 4

Please see the answers (I recommend mine ^_;-) ) to this similar question.