var rc = HostFactory.Run(x => {

                x.Service<ProgramService>(s =>
                {
                    s.ConstructUsing(name => new ProgramService());
                    s.WhenStarted(p => p.Start());
                    s.WhenStopped(p => p.Stop());
                });

                x.RunAsLocalSystem();

                x.SetDescription("Windows Program Monitor Service Host");
                x.SetDisplayName("Windows Program Monitor Service");
                x.SetServiceName("Windows Program Monitor Service");
            });

readonly Timer _timer;
public ()
{
    _timer = new Timer(1000) { AutoReset = true };
    _timer.Elapsed +=
        (sender, eventArgs) =>
        Console.WriteLine($"It is {DateTime.Now} and all is well");
}

public void Start()
{
    _timer.Start();
}

public void Stop()
{
    _timer.Stop();
}

public string GetMainProcess()
{

    var processlist = Process.GetProcesses();
    var result = "";

    foreach (Process process in processlist)
    {
        if (!String.IsNullOrEmpty(process.MainWindowTitle))
        {
            result += $"Process: {process.ProcessName}, Window title: {process.MainWindowTitle},Start Time : {process.StartTime} ,Running Time: {DateTime.Now - process.StartTime}n";
        }
    }
    return result;
}