客戶端上的wcf服務器啓動方法

Question

我在我的WCF服務器上執行回調的方法如下所示。這工作正常，包括回調。

但是我如何從服務器啓動客戶端上的方法的執行。即代碼段C＃按鈕代碼我想有下面。

目前我得到的錯誤是：

Object reference not set to an instance of an object. 

可能是我的架構是所有的錯在這裏和WCF客戶端也需要有建立在一個WCF服務器？ WCF服務器上

C＃方法WCF服務器上

public void ChatToServer(string texttoServer) // send some text to the server 
{ 
    Logging.Write_To_Log_File("Entry", MethodBase.GetCurrentMethod().Name, "", "", "", 1); 

    try 
    { 
     IMyContractCallBack callback = OperationContext.Current.GetCallbackChannel<IMyContractCallBack>(); 
     callback.ChatToClient("your message: " + texttoServer + " has been recieved");   

     Logging.Write_To_Log_File("Exit", MethodBase.GetCurrentMethod().Name, "", "", "", 1); 

    } 
    catch (Exception ex) 
    { 
     Logging.Write_To_Log_File("Error", MethodBase.GetCurrentMethod().Name, "", "", ex.ToString(), 2); 
    } 

} 

C＃按鈕的代碼，我想有

private void radButtonSend_Click(object sender, EventArgs e) 
     { 

      try 
      { 
       Logging.Write_To_Log_File("Entry", MethodBase.GetCurrentMethod().Name, "", "", "", 1); 

       IMyContractCallBack callback = OperationContext.Current.GetCallbackChannel<IMyContractCallBack>(); 
       callback.ChatToClient(radTextBox2Send.Text); 

       Logging.Write_To_Log_File("Exit", MethodBase.GetCurrentMethod().Name, "", "", "", 1); 
      } 

      catch (Exception ex) 
      { 
       Logging.Write_To_Log_File("Error", MethodBase.GetCurrentMethod().Name, "", "", ex.ToString(), 2); 
       MessageBox.Show(ex.Message.ToString()); 

      } 

     } 

WCF服務配置

<?xml version="1.0" encoding="utf-8" ?> 
<configuration> 
    <system.serviceModel> 
    <behaviors> 
     <serviceBehaviors> 
     <behavior name="Throttled"> 
      <serviceMetadata httpGetEnabled="False" /> 
      <serviceDebug includeExceptionDetailInFaults="False" /> 
      <serviceThrottling maxConcurrentCalls="100000" maxConcurrentInstances="100000" maxConcurrentSessions="100000" /> 
     </behavior> 
     </serviceBehaviors> 
    </behaviors> 
    <services> 
    <service name="WCFService.WCFJobsLibrary" behaviorConfiguration="Throttled" > 
     <host> 
     <baseAddresses> 
      <add baseAddress="http://localhost:8732/Design_Time_Addresses/WCFService/WCFJobsLibrary/" /> 
     </baseAddresses> 
     </host> 
     <endpoint name ="duplexendpoint" 
      address ="" 
      binding ="wsDualHttpBinding" 
      contract ="WCFService.IWCFJobsLibrary"/> 
     <endpoint name ="MetaDataTcpEndpoint" 
       address="mex" 
       binding="mexHttpBinding" 
       contract="IMetadataExchange"/> 
    </service> 
    </services> 
    </system.serviceModel> 
    <system.webServer> 
    <modules runAllManagedModulesForAllRequests="true"/> 
    </system.webServer> 
</configuration> 

WCF客戶端配置

<configuration> 
    <system.serviceModel> 
    <bindings> 
     <wsDualHttpBinding> 
     <binding name="duplexendpoint" closeTimeout="00:01:00" openTimeout="00:01:00" 
      receiveTimeout="00:10:00" sendTimeout="00:01:00" bypassProxyOnLocal="false" 
      transactionFlow="false" hostNameComparisonMode="StrongWildcard" 
      maxBufferPoolSize="524288" maxReceivedMessageSize="65536" messageEncoding="Text" 
      textEncoding="utf-8" useDefaultWebProxy="true"> 
      <readerQuotas maxDepth="32" maxStringContentLength="8192" maxArrayLength="16384" 
      maxBytesPerRead="4096" maxNameTableCharCount="16384" /> 
      <reliableSession ordered="true" inactivityTimeout="00:10:00" /> 
      <security mode="Message"> 
      <message clientCredentialType="Windows" negotiateServiceCredential="true" 
       algorithmSuite="Default" /> 
      </security> 
     </binding> 
     </wsDualHttpBinding> 
    </bindings> 
    <client> 
     <endpoint address="http://localhost:8732/Design_Time_Addresses/WCFService/WCFJobsLibrary/" 
     binding="wsDualHttpBinding" bindingConfiguration="duplexendpoint" 
     contract="ServiceReference1.IWCFJobsLibrary" name="duplexendpoint"> 
     </endpoint> 
    </client> 
    </system.serviceModel> 
</configuration> 

合同

namespace WCFService 
{ 
    [ServiceContract(CallbackContract = typeof(IMyContractCallBack))] 
    public interface IWCFJobsLibrary 
    { 
     [OperationContract(IsOneWay = true)] 
     void ChatToServer(string texttoServer); // send some text to the server 

     [OperationContract(IsOneWay = true)] 
     void NormalFunction(); 

     [OperationContract(IsOneWay = false)] 
     int ChatToServerWithResult(string texttoServer); // send some text to the server and send back success indication 

    } 

    public interface IMyContractCallBack 
    { 
     [OperationContract(IsOneWay = true)] 
     void CallBackFunction(string str); 


     [OperationContract(IsOneWay = true)] 
     void ChatToClient(string str); 

    } 
} 

Answer 1

在你的情況我建議你使用wsDualHttpBinding：一個安全，可互操作的結合，設計用於與雙工服務合同使用這允許服務和客戶端發送和接收消息。 請參閱示例：http://blog.binarymist.net/2010/05/23/duplex-communication-and-callbacks-in-wcf/