Question

Ive got a service which currently i believe is running every 10 min, but i want it to run at 7pm every day, what do i need to change? ….

 private Timer _timer;
    private DateTime _lastRun = DateTime.Now;

    protected override void OnStart(string[] args)
    {
        _timer = new Timer(10 * 60 * 1000); // every 10 minutes??
        _timer.Elapsed += new System.Timers.ElapsedEventHandler(timer_Elapsed);
    }

    private void timer_Elapsed(object sender, System.Timers.ElapsedEventArgs e)
    {

        if (_lastRun.Date < DateTime.Now.Date)
        {
            // stop the timer 
            _timer.Stop();               

            try
            {
                SmartImportService.WebService.WebServiceSoapClient test = new WebService.WebServiceSoapClient();
                test.Import();
            }
            catch (Exception ex) { }

            _lastRun = DateTime.Now;
            _timer.Start();
        }
    }

Answer 1

Replacing:

if (_lastRun.Date < DateTime.Now.Date)
{
}

with:

DateTime startAt = DateTime.Today.AddHours(19);
if (_lastRun < startAt && DateTime.Now >= startAt)
{
}

will probably do the trick. But I would prefer to use a scheduled task as has been suggested already