// Wrap event invocations inside a protected virtual method
// to allow derived classes to override the event invocation behavior
protected virtual void OnTimerTimer(TimerEventArgs e)
{
// Make a temporary copy of the event to avoid possibility of
// a race condition if the last subscriber unsubscribes
// immediately after the null check and before the event is raised.
EventHandler<TimerEventArgs> handler = RaiseTimerEvent;
// Event will be null if there are no subscribers
if (handler != null)
{
// Format the string to send inside the TimerEventArgs parameter
e.Message += String.Format(" at {0}", DateTime.Now.ToString());
// Use the () operator to raise the event.
handler(this, e);
}
}
// Define what actions to take when the event is raised.
void HandleTimerEvent(object sender, TimerEventArgs e)
{
Console.WriteLine(id + " received this message: {0}", e.Message);
}