windows8 后台任务

后台任务示例

这个示例显示了如何创建并注册后台任务使用Windows运行后台任务API。

一个后台任务是由于系统或时间事件,可以由一个或多个条件的限制。当一个后台任务被触发,其关联处理程序运行和执行任务的工作背景。一个后台任务可以运行一个应用程序,即使注册了后台任务被暂停。

这个示例演示了以下工作:

•创建和注册后台任务用c#编写的或JavaScript。

•创建一个后台任务,由系统事件触发。

•添加一个条件,限制后台任务运行只有当条件实际上是。

•报告后台任务进度和完成到前台应用程序。

•处理取消后台任务。

•初始化任务进程以及背景完成处理程序在启动应用程序时。

 private void OnProgress(IBackgroundTaskRegistration sender, BackgroundTaskProgressEventArgs e)
        {
            //
            // Update the UI with progress reported by the background task.
            //
            SampleDispatcher.InvokeAsync(CoreDispatcherPriority.Normal,
                                         (task, args) =>
                                         {
                                             var taskRegistration = task as IBackgroundTaskRegistration;
                                             var progressArgs = args.Context as BackgroundTaskProgressEventArgs;

                                             if ((task != null) && (args != null))
                                             {
                                                 switch (taskRegistration.Name)
                                                 {
                                                     case SampleBackgroundTaskName:
                                                         SampleBackgroundTaskProgress.Text = "Progress: " + progressArgs.Progress + "%";
                                                         break;
                                                     case SampleBackgroundTaskWithConditionName:
                                                         SampleBackgroundTaskWithConditionProgress.Text = "Progress: " + progressArgs.Progress + "%";
                                                         break;
                                                     case ServicingCompleteTaskName:
                                                         ServicingCompleteProgress.Text = "Progress: " + progressArgs.Progress + "%";
                                                         break;
                                                     case TimeTriggeredTaskName:
                                                         TimeTriggeredBackgroundTaskProgress.Text = "Progress: " + progressArgs.Progress + "%";
                                                         break;
                                                 }
                                             }
                                         },
                                         sender,
                                         e);

        } 

 完整示例 /Files/risk/windows8/后台任务sample.rar