c# - 摆脱 try/catch - 从消息队列中读取

Question

如何修改以下代码块，使其不依赖于 try/catch block 和 IOTimeout。此函数每 1 分钟调用一次。所以我只想处理在上次调用后排队的 ID 列表。

如果我在队列中没有消息等待时收到空值，那会解决我的问题，但 API http://msdn.microsoft.com/en-us/library/system.messaging.messagequeue.receive.aspx显示接收的所有签名都是同步的(我无法阻止线程)或带有 MessageQueueException 异常，我必须通过 try/catch block 来利用这些异常。在阅读了一些建议不要使用 try/catch 来控制程序流的文章后，我想避免这种情况。

    #pragma warning disable
    public void ConsumeEvents2()
    {
        var listOfJobs = new List<int>();

        try {
            while (true) { 
                // receive all messages and add in a list to process later
                Message message = messageQueue.Receive(new TimeSpan(0,0,3));
                JobEvent evt = (JobEvent)message.Body;
                listOfJobs.Add(evt.DataNumber);
            }
        } catch (MessageQueueException e) {
            if (e.MessageQueueErrorCode == MessageQueueErrorCode.IOTimeout) {
                // process the numbers received
                ProcessJobList(listOfJobs);
                return;
            }
            throw;
        }

    }
    #pragma warning restore

Answer 1

尽量不要直接访问它，看一下微软的这段代码-

using System;
using System.Windows.Controls;
using System.Windows.Messaging;

namespace ReceivingApplication
{
  public partial class Receiver : UserControl
  {
    public Receiver()
    {
        InitializeComponent();

        LocalMessageReceiver messageReceiver =
            new LocalMessageReceiver("receiver",
            ReceiverNameScope.Global, LocalMessageReceiver.AnyDomain);
        messageReceiver.MessageReceived += messageReceiver_MessageReceived;
        try
        {
            messageReceiver.Listen();
        }
        catch (ListenFailedException)
        {
            output.Text = "Cannot receive messages." + Environment.NewLine +
                "There is already a receiver with the name 'receiver'.";
        }
    }

    private void messageReceiver_MessageReceived(
        object sender, MessageReceivedEventArgs e)
    {
        e.Response = "response to " + e.Message;
        output.Text =
            "Message: " + e.Message + Environment.NewLine +
            "NameScope: " + e.NameScope + Environment.NewLine +
            "ReceiverName: " + e.ReceiverName + Environment.NewLine +
            "SenderDomain: " + e.SenderDomain + Environment.NewLine +
            "Response: " + e.Response;
    }
  }
}