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copied!<p>If I understand your question correctly, you want to call a function every minute but have it synchronized with the system clock. This isn't entirely straight forward. I'll tell you my approach and we'll go from there.</p> <p>The <a href="http://msdn.microsoft.com/en-us/library/system.timers.timer.aspx" rel="nofollow"><code>Timer</code></a> class is a good way of executing a given function at an X interval. The problem with this is you want to keep it in sync with when a minute elapses according to the system clock. So we need to make sure we start the timer only when a minute elapses by the clock. Here are a few approaches.</p> <ol> <li><p>Let the timer fire every second; but before we let it do anything we check to see if a minute has passed according to the clock. If so; then we let it proceed. That would look something like this:</p> <pre><code>Module TimerExample Private _previousTime As DateTime = DateTime.Now Sub Main() Dim timer As New System.Timers.Timer(1000) AddHandler timer.Elapsed, AddressOf TimeElapsed timer.Start() 'Run a loop so the console application doesn't quit Application.Run() End Sub Sub TimeElapsed(sender As Object, args As ElapsedEventArgs) Dim now As DateTime = DateTime.Now If now.Minute > _previousTime.Minute Then 'A minute elapsed. Do your code here Console.WriteLine("A minute elapsed!") End If _previousTime = now End Sub End Module </code></pre> <p>This might be an acceptable solution for you. The only "downside" is that the timer is firing every second; but it doesn't do anything until a minute has elapsed.</p></li> <li><p>Another alternative might be to use two timers. Use the first timer in a similar fasion to the first example; but use it to start another timer that only elapses every minute. Once you start the second timer, let the first one stop. The only positive to this approach is a timer is only firing every minute. The negatives are the timer will probably start drifting from the system clock over a long period of time. The first example is a better approach; but this is an option if letting a timer fire every second is too expensive (though I really doubt it would be).</p></li> </ol> <p>Another thing you may want to handle; maybe not; is when a user changes the system time. You can handle time <a href="http://msdn.microsoft.com/en-us/library/microsoft.win32.systemevents.timechanged.aspx" rel="nofollow"><code>SystemEvents.TimeChanged</code></a> to know when that happens.</p>

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