How to use the .NET Timer class to trigger an event at a specific time?

Question

I would like to have an event triggered in my app which runs continuously during the day at a certain time, say at 4:00pm. I thought about running the timer every second and

Answer 1

You can use Task Sceduler on windows See daily trigger example for detail.

or use bellow code if you want wrote it yourself:

public void InitTimer()
{
    DateTime time = DateTime.Now;
    int second = time.Second;
    int minute = time.Minute;
    if (second != 0)
    {
        minute = minute > 0 ? minute-- : 59;
    }

    if (minute == 0 && second == 0)
    {
        // DoAction: in this function also set your timer interval to 24 hours
    }
    else
    {
        TimeSpan span = //new daily timespan, previous code was hourly: new TimeSpan(0, 60 - minute, 60 - second);
        timer.Interval = (int) span.TotalMilliseconds - 100; 
        timer.Tick += new EventHandler(timer_Tick);
        timer.Start();
    }
}

void timer_Tick(object sender, EventArgs e)
{
    timer.Interval = ...; // 24 hours
    // DoAction
}