后台工作者线程问题 [英] Background Worker Thread Problem

问题描述

我在应用程序中使用后台工作程序

I am using background worker in my Application

我的代码

 void CreateThreadForEachServer()
 {
    DataAccess oDA = new DataAccess();

    List<Server> allServerData = oDA.GetAllServers();

    foreach (Server serverData in allServerData)
    {
        backgroundWorker = new BackgroundWorker();

        backgroundWorker.DoWork += new DoWorkEventHandler(backgroundWorker_DoWork);

        backgroundWorker.RunWorkerAsync(serverData);

    }
}

void backgroundWorker_DoWork(object sender, DoWorkEventArgs e)
{
    Server server = (Server)e.Argument;
    CreateSnapshotForEachServer(server);
}

void CreateSnapshotForEachServer(Server server)
{
    DataAccess oDA = new DataAccess();
    MsmqMessageFormat message = new MsmqMessageFormat();

    try
    {
        message = new Queue().ReadMessageFromMSMQ(server.ServerName);
    }
    catch
    {
    }
 }

我的问题是何时调用此方法

My problem is when I am calling this method

 try
 {
     message = new Queue().ReadMessageFromMSMQ(server.ServerName);
 }
 catch
 {
 }

在后台工作人员中，我无法从MSMQ中读取消息就无法调用此方法

in a background worker then i can not able to call this method just read a message from MSMQ

但是当我不能使用后台工作程序时，只需在这样的简单线程中调用此方法

But when i can't use background worker just call this method in simple thread like this

void CreateThreadForEachServer()
{
    DataAccess oDA = new DataAccess();

    List<Server> allServerData = oDA.GetAllServers();

    foreach (Server serverData in allServerData)
    {
        ThreadStart t = delegate { CreateSnapshotForEachServer(serverData); };
        Thread td = new Thread(t);                
        td.Priority = ThreadPriority.Highest;
        td.Start();
    }
}

然后正确调用此方法

try
{
    message = new Queue().ReadMessageFromMSMQ(server.ServerName);
}
catch
{
}

我的Queue类的后台工作程序是什么问题

what is the problem with background worker my Queue class is like this

 class Queue
 {
     public MsmqMessageFormat ReadMessageFromMSMQ(string queueName)
     {
         MessageQueue messageQueue = null;

         messageQueue = new MessageQueue(@".\Private$\" + queueName);

         messageQueue.Formatter = new XmlMessageFormatter(new Type[] { typeof(MsmqMessageFormat) });

         System.Messaging.Message msg = null;
         System.Messaging.Message[] allMessages = messageQueue.GetAllMessages();

         if (allMessages.Length > 0)
         {
             msg = messageQueue.Receive();

             MsmqMessageFormat readMessage = (MsmqMessageFormat)(msg.Body);

             return readMessage;
         }
         else
         {
             return null;
         }
     }
 }

和MsmqMessageFormat类是这样的

and MsmqMessageFormat class is like this

[Serializable]
public class MsmqMessageFormat
{      
    public Zvol Zvol { get; set;}
    public List<PolicyInterval> listPolicyIntervalInfo = new List<PolicyInterval>(); 
}

推荐答案

您能否阐明应用程序的上下文?

Can you clarify on the context of your application?

这是Windows Forms应用程序吗?控制台应用程序?还是WPF?

Is it a Windows Forms app? Console app? Or WPF?

它可能与线程的公寓状态有关. BackgroundWorker使用的线程默认为MTA(并且您不能覆盖它).虽然手动创建的线程可能会将apartmentstate设置为STA.

It could have something to do with the apartmentstate of the thread. Threads used by the BackgroundWorker are defaulted to MTA (and you can't override it). While threads created manually could have there apartmentstate set to STA.

这篇关于后台工作者线程问题的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！