问题
Using C#, how may I get the time remaining (before the elapse event will occur) from a System.Timers.Timer
object?
In other words, let say I set the timer interval to 6 hours, but 3 hours later, I want to know how much time is remaining. How would I get the timer object to reveal this time remaining?
回答1:
The built-in timer doesn't provide the time remaining until elapse. You'll need to create your own class which wraps a timer and exposes this info.
Something like this should work.
public class TimerPlus : IDisposable
{
private readonly TimerCallback _realCallback;
private readonly Timer _timer;
private TimeSpan _period;
private DateTime _next;
public TimerPlus(TimerCallback callback, object state, TimeSpan dueTime, TimeSpan period)
{
_timer = new Timer(Callback, state, dueTime, period);
_realCallback = callback;
_period = period;
_next = DateTime.Now.Add(dueTime);
}
private void Callback(object state)
{
_next = DateTime.Now.Add(_period);
_realCallback(state);
}
public TimeSpan Period
{
get
{
return _period;
}
}
public DateTime Next
{
get
{
return _next;
}
}
public TimeSpan DueTime
{
get
{
return _next - DateTime.Now;
}
}
public bool Change(TimeSpan dueTime, TimeSpan period)
{
_period = period;
_next = DateTime.Now.Add(dueTime);
return _timer.Change(dueTime, period);
}
public void Dispose()
{
_timer.Dispose();
}
}
回答2:
I am aware, that the topic is more than 3 years old. However I came across it while tackling exactly the same problem.
Inspired by Samuel Neff, I came up with a WinForms-less solution by extending the standard System.Timers.Timer class:
public class TimerPlus : System.Timers.Timer
{
private DateTime m_dueTime;
public TimerPlus() : base()
{
this.Elapsed += this.ElapsedAction;
}
protected new void Dispose()
{
this.Elapsed -= this.ElapsedAction;
base.Dispose();
}
public double TimeLeft
{
get
{
return (this.m_dueTime - DateTime.Now).TotalMilliseconds;
}
}
public new void Start()
{
this.m_dueTime = DateTime.Now.AddMilliseconds(this.Interval);
base.Start();
}
private void ElapsedAction(object sender, System.Timers.ElapsedEventArgs e)
{
if (this.AutoReset)
{
this.m_dueTime = DateTime.Now.AddMilliseconds(this.Interval);
}
}
}
I hope it helps.
回答3:
I guess the best method is to hold the start time in a variable and then calculate the elapsed time as
TimeSpan t = DateTime.Now - StartTime;
来源:https://stackoverflow.com/questions/2278525/system-timers-timer-how-to-get-the-time-remaining-until-elapse