Windows Phone：退出应用程序后如何保持计时器运行？

Question

I want to write an app to show a countdown Timer. When I exit the application by pressing Home or search buttons timer will stop till I go back to the application. Here is my Code:

 public Page1()
{
 InitializeComponent();       
 DispatcherTimer dispatcherTimer = new DispatcherTimer();
 dispatcherTimer.Interval = new TimeSpan(0, 0, 0, 1, 0);
 dispatcherTimer.Tick += new EventHandler(dispatcherTimer_Tick);
 dispatcherTimer.Start();
}

private void dispatcherTimer_Tick(object sender, EventArgs e)
{
   //Till timer is greater than 0 show timer.
}

How can I use the timer in a way that it keeps counting (running) even when I exited the application?

Answer 1

Save the time when you started the timer in the ApplicationSettings . When the app resumes (activated or re-launched), check the time diff and either restart the timer from the remaining time or show the timer as stopped.

Answer 2

在Windows服务中嵌入WCF或Web API服务（Windows服务计时器示例） ，使用此WCF / Web API服务，您可以控制行为而无需重新启动服务。