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

The issue with the accepted answer is that checking the status of an service that isn't installed will throw. The IsService Method I'm using looks like this:

    private bool IsService(string name)
    {
        if (!Environment.UserInteractive) return true;
        System.ServiceProcess.ServiceController sc = new System.ServiceProcess.ServiceController(name);
        try
        {
            return sc.Status == System.ServiceProcess.ServiceControllerStatus.StartPending;
        }
        catch(InvalidOperationException)
        {
            return false;
        }
    }

Which should work more reliably than just checking Environment.UserInteractive