ServiceAsConsoleMain.cs

static class Program
{
    static void Main()
    {
        var servicesToRun = new ServiceBase[] { new YourService() };

        // Run as service
        if (!Environment.UserInteractive)
        {
            ServiceBase.Run(servicesToRun);
        }
        // Run as console
        else
        {
            Type type = typeof(ServiceBase);

            var onStartMethod = type.GetMethod("OnStart", BindingFlags.Instance | BindingFlags.NonPublic);
            foreach (var service in servicesToRun)
            {
                onStartMethod.Invoke(service, new object[] { null });
            }

            Console.ReadLine();

            var onStopMethod = type.GetMethod("OnStop", BindingFlags.Instance | BindingFlags.NonPublic);
            foreach (var service in servicesToRun)
            {
                onStartMethod.Invoke(service, new object[] { null });
            }
        }
    }
}