收聽msmq隊列

Question

以下是我用於收聽Windows窗體消息的代碼。

我注意到，當我點擊send它發送消息給MyQueue，但當時我希望事件mq_ReceiveCompleted(object sender, ReceiveCompletedEventArgs e)應該被調用，但它不是，換句話說，我試圖從Windows窗體訂閱MyQueue 。只是想知道我是否遺漏了代碼中的某些東西：

public class Form1 : System.Windows.Forms.Form 
{ 
    public System.Messaging.MessageQueue mq; 
    public static Int32 j=0; 

    public Form1() 
    { 
     // Required for Windows Form Designer support 
     InitializeComponent(); 

     // Queue Creation 
     if(MessageQueue.Exists(@".\Private$\MyQueue")) 
     mq = new System.Messaging.MessageQueue(@".\Private$\MyQueue"); 
     else 
     mq = MessageQueue.Create(@".\Private$\MyQueue"); 

     mq.ReceiveCompleted += new ReceiveCompletedEventHandler(mq_ReceiveCompleted); 
     mq.BeginReceive(); 
    } 

    [STAThread] 
    static void Main() 
    { 
     Application.Run(new Form1()); 
    } 

    private void btnMsg_Click(object sender, System.EventArgs e) 
    { 
     // SendMessage(Handle, 1, 0, IntPtr.Zero); 
     System.Messaging.Message mm = new System.Messaging.Message(); 
     mm.Body = txtMsg.Text; 
     mm.Label = "Msg" + j.ToString(); 
     j++; 
     mq.Send(mm); 
    } 

    void mq_ReceiveCompleted(object sender, ReceiveCompletedEventArgs e) 
    { 
     //throw new NotImplementedException(); 
    } 

    private void btnRcv_Click(object sender, System.EventArgs e) 
    { 
     System.Messaging.Message mes; 
     string m; 

     try 
     { 
      mes = mq.Receive(new TimeSpan(0, 0, 3)); 
      mes.Formatter = new XmlMessageFormatter(new String[] {"System.String,mscorlib"}); 
      m = mes.Body.ToString(); 
     } 
     catch 
     { 
      m = "No Message"; 
     } 
     MsgBox.Items.Add(m.ToString()); 
    } 
} 

Answer 1

請參閱MSDN's example on how to use the ReceiveCompletedEventHandler。

他們有一個控制檯應用程序，其中Main()與Form1()的作用相同，但您的處理程序沒有任何代碼。你已經說過它不會回調你的事件委託，但是也許在構造函數中檢查你的隊列名是否正確。

使用一個新的控制檯應用程序 MSDN的示例代碼首先測試您的環境，然後回到你的WinForms代碼與任何教訓考慮。

private static void MyReceiveCompleted(Object source, 
     ReceiveCompletedEventArgs asyncResult) 
    { 
     MessageQueue mq = (MessageQueue)source; 
     Message m = mq.EndReceive(asyncResult.AsyncResult); 

     Console.WriteLine("Message: " + (string)m.Body); 
     mq.BeginReceive();  
     return; 
    } 

如果要檢查隊列並獲得一個點擊按鈕的消息，你可以簡單地聲明mq.BeginReceive();移動到位的.Receive()的btnRcv_Click();