小编Tim*_*may的帖子

当我尝试在Windows Phone 7.5中添加一个周期性任务时,它会给我一个"BNS错误:已经添加了此类型的最大ScheduledActions数".我没有添加任何周期性任务时出错.该代码在Windows Phone 8上运行正常,但在WP7.5上引发了此错误.该应用程序还安排提醒和警报.

string periodicTaskName = "myperiodictask";
        PeriodicTask periodicTask = ScheduledActionService.Find(periodicTaskName) as PeriodicTask;
        if (periodicTask != null)
        {
            try
            {
                ScheduledActionService.Remove(periodicTaskName);
            }
            catch (Exception)
            { }
        }
        periodicTask = new PeriodicTask(periodicTaskName);
        periodicTask.Description = "Updates LiveTile, Sessions and Assignments";
        periodicTask.ExpirationTime = DateTime.Now.AddDays(10);
        try
        {
            ScheduledActionService.Add(periodicTask);
        }
        catch (InvalidOperationException exception)
        {
            if (exception.Message.Contains("BNS Error: The action is disabled"))
                MessageBox.Show("Background agents have been disabled by the user.");
            if (exception.Message.Contains("BNS Error: The maximum number of ScheduledActions of this type have already been …