在後臺運行方法

Question

我正在開發一個應用程序，其中應用程序會向用戶提問一個問題，其中有幾個 - 例如詢問用戶是否要評估應用程序。我需要運行此方法，但它大大增加了應用程序啓動時間。我怎樣才能在後臺運行這個？我檢查了堆棧溢出的其他問題沒有太多的幫助。

簡稱爲：：

checkUserStats(); 

方法：

private void checkUserStats() 
{ 
    // Load settings from IsolatedStorage first 
    try 
    { 
     userRemindedOfRating = Convert.ToBoolean(settings["userRemindedOfRating"].ToString()); 
    } 
    catch (Exception) 
    { 
     userRemindedOfRating = false; 
    } 

    try 
    { 
     wantsAndroidApp = Convert.ToBoolean(settings["wantsAndroidApp"].ToString()); 
    } 
    catch (Exception) 
    { 
     wantsAndroidApp = false; 
    } 

    //Check if the user has added more 3 notes, if so - remind the user to rate the app 
    if (mainListBox.Items.Count.Equals(4)) 
    { 
     //Now check if the user has been reminded before 
     if (userRemindedOfRating.Equals(false)) 
     { 
      //Ask the user if he/she wants to rate the app 
      var ratePrompt = new MessagePrompt 
      { 
       Title = "Hi!", 
       Message = "I See you've used the app a little now, would u consider doing a review in the store? It helps a lot! Thanks!:)" 
      }; 
      ratePrompt.IsCancelVisible = true; 
      ratePrompt.Completed += ratePrompt_Completed; 
      ratePrompt.Show(); 

      //Save the newly edited settings 
      try 
      { 
       settings.Add("userRemindedOfRating", true); 
       settings.Save(); 
      } 
      catch (Exception) 
      { 
      } 

      //Update the in-memory boolean 
      userRemindedOfRating = true; 
     } 
     else if (userRemindedOfRating.Equals(true)) 
     { 
      // Do nothing 
     } 
    } 
    else 
    { 
    } 

    // Ask the user if he/she would like an android app 
    if (wantsAndroidApp.Equals(false)) 
    { 
     // We haven't asked the user yet, ask him/her 
     var androidPrompt = new MessagePrompt 
     { 
      Title = "Question about platforms", 
      Message = "Hi! I just wondered if you wanted to have this app for android? If so, please just send me a quick email. If enough people wants it, I'll create it:)" 
     }; 
     androidPrompt.IsCancelVisible = true; 
     androidPrompt.Completed += androidPrompt_Completed; 
     androidPrompt.Show(); 

     //Save the newly edited settings 
     try 
     { 
      settings.Add("wantsAndroidApp", true); 
      settings.Save(); 
     } 
     catch (Exception) 
     { 
     } 

     //Update the in-memory boolean 
     wantsAndroidApp = true; 
    } 
    else if (wantsAndroidApp.Equals(true)) 
    { 
     // We have asked the user already, do nothing 
    } 
} 

我現在嘗試這樣做：在後臺運行需要的方法

使用：

using System.ComponentModel; 

聲明：

BackgroundWorker worker; 

初始化：

worker = new BackgroundWorker(); 
worker.DoWork+=worker_DoWork; 

方法：

private void worker_DoWork(object sender, DoWorkEventArgs e) 
{ 
    checkUserStats(); 
} 

但它會導致System.UnauthorizedAccessException的：無效在我app.xaml.cs跨線程訪問

Answer 1

你可以使用後臺工作線程並將你的方法調用放入它裏面

'Silverlight BackgroundWorker類提供了一種在後臺線程上運行耗時操作的簡單方法。 BackgroundWorker類使您能夠檢查操作的狀態，並讓您取消操作。 當您使用BackgroundWorker類時，您可以在Silverlight用戶界面中指示操作進度，完成和取消。例如，您可以檢查後臺操作是完成還是取消，並向用戶顯示消息。'

你基本上只需要初始化一個backgroundworker對象並訂閱它的DoWork事件。

併爲您的異常

private void worker_DoWork(object sender, DoWorkEventArgs e) 
    { 
     Dispatcher.BeginInvoke(() => 
     { 
     checkUserStats(); 
     }); 
    } 

補救措施只是給看看這個msdn文章 和一個more文章。