如何知道使用異步時Task或Void方法是否仍在運行

Question

我想使用異步並等待，而我的問題是它不會等待後臺進程完成。也許你想知道爲什麼我不能同步運行應用程序？ 我想盡快完成我的任務的一部分，其餘的可以等待，如本例中所示。 謝謝你們的幫助！ =）

class Program 
{ 
    static void Main(string[] args) 
    { 
     Run(); 
     //Problem or Maybe Not? Needs this 
     //So that my application won't close immediately 
     Console.ReadLine(); 
    } 

    private async static void Run() 
    { 
     Task<bool> TBool = ProcessRecords(); 

     if (await TBool) 
     { 
      //Problem #1 This Line Doesn't Show 
      Console.WriteLine("End of Code"); 
      //SHould be safe to close the application by Now 
      //But goes through here not waiting for the return 
      //of the last process. 

      Environment.Exit(0); 

      //My temporary solution is to indicate a Task.Delay(80000) 
      //to make sure that all the logging in the background 
      //are all done. I dont know if there is a function that shows 
      //that there are task running on the background or any 
      //other workaroung will help. =) thanks 
     } 

    } 

    private async static Task<bool> ProcessRecords() 
    { 
     Task newTask = null; 
     //Loop through all the records and send 
     //all the records to MQ ASAP 
     for (int x = 0; x < 10; x++) 
     { 
      //I wont wait for this Task so 
      //I can send the next record 
      newTask = SendToMQ(x); 
     } 
     //I only need to wait for the last Task to 
     //indicate that I can exit the system 
     //as soon as it finish 
     //Problem #2 The Console.WriteLine doesnt show the last record. 
     await newTask; 
     return true; 
    } 

    private async static Task SendToMQ(int count) 
    { 
     //actual sending of message (Important) 
     await Task.Delay(1000); 
     //Process of Logging Connect to DB etc, (Not so Important, but takes most of the time) 
     await LoggingRecord(); 
     Console.Clear(); 
     Console.WriteLine("Done Processing " + count.ToString() + " records"); 
    } 

    //Logging of each record 
    private async static Task LoggingRecord() 
    { 
     await Task.Delay(5000); 
     //Problem #3 This Line Doesn't Show 
     Console.WriteLine("Last Log Finished"); 
    } 
} 

Answer 1

你應該用等待儘可能：

await Run(); 

然而，在這種情況下，你不能，那麼你必須使用等待

static void Main(string[] args) 
{ 
    Run().Wait(); 

    //Problem or Maybe Not? Needs this 
    //So that my application won't close immediately 
    //Console.ReadLine(); 
} 

// note the return type is Task 
private async static Task Run() 
{ 
... 
} 

在ProcessRecords（）你有以下行 - 我不太清楚你的意思，所以我沒有解決它：

//Problem #2 The Console.WriteLine doesnt show the last record. 

個

上面打印出

Done Processing 9 records 
End of Code