上接稳扎稳打Silverlight(23) - 2.0通信之调用WCF的双向通信(Duplex Service)

<UserControl x:Class="Silverlight20.Communication.DuplexService" 
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"    
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"> 
        <StackPanel HorizontalAlignment="Left" Margin="5"> 
         
                <TextBox x:Name="txtStockCode" Text="请输入股票代码" Margin="5" /> 
                <Button x:Name="btnSubmit" Content="获取股票信息" Click="btnSubmit_Click" Margin="5" /> 
                <Button x:Name="btnStop" Content="停止获取" Click="btnStop_Click"    Margin="5" /> 
                <TextBlock x:Name="lblStockMessage" Margin="5" /> 
         
        </StackPanel> 
</UserControl>

using System; 
using System.Collections.Generic; 
using System.Linq; 
using System.Net; 
using System.Windows; 
using System.Windows.Controls; 
using System.Windows.Documents; 
using System.Windows.Input; 
using System.Windows.Media; 
using System.Windows.Media.Animation; 
using System.Windows.Shapes; 
 
using System.ServiceModel; 
using System.ServiceModel.Channels; 
using System.Threading; 
using System.IO; 
 
namespace Silverlight20.Communication 
{ 
         public partial  class DuplexService : UserControl 
        { 
                SynchronizationContext _syncContext; 
 
                 // 是否接收服务端发送过来的消息 
                 bool _status =  true; 
 
                 public DuplexService() 
                { 
                        InitializeComponent(); 
                } 
 
                 private  void btnSubmit_Click( object sender, RoutedEventArgs e) 
                { 
                        _status =  true; 
 
                         // UI 线程 
                        _syncContext = SynchronizationContext.Current; 
 
                        PollingDuplexHttpBinding binding =  new PollingDuplexHttpBinding() 
                        { 
                                 // InactivityTimeout - 服务端与客户端在此超时时间内无任何消息交换的情况下，服务会关闭其会话 
                                InactivityTimeout = TimeSpan.FromMinutes(1) 
                        }; 
 
                         // 构造 IDuplexSessionChannel 的信道工厂 
                        IChannelFactory<IDuplexSessionChannel> factory = 
                                binding.BuildChannelFactory<IDuplexSessionChannel>( new BindingParameterCollection()); 
 
                         // 打开信道工厂 
                        IAsyncResult factoryOpenResult = 
                                factory.BeginOpen( new AsyncCallback(OnOpenCompleteFactory), factory); 
 
                         if (factoryOpenResult.CompletedSynchronously) 
                        { 
                                 // 如果信道工厂被打开的这个 异步操作 已经被 同步完成 则执行下一步 
                                CompleteOpenFactory(factoryOpenResult); 
                        } 
                } 
 
                 private  void btnStop_Click( object sender, RoutedEventArgs e) 
                { 
                        _status =  false; 
                } 
 
                 void OnOpenCompleteFactory(IAsyncResult result) 
                { 
                         // 该异步操作已被同步完成的话则不做任何操作，反之则执行下一步 
                         if (result.CompletedSynchronously) 
                                 return; 
                         else 
                                CompleteOpenFactory(result); 
                } 
 
                 void CompleteOpenFactory(IAsyncResult result) 
                { 
                        IChannelFactory<IDuplexSessionChannel> factory = result.AsyncState  as IChannelFactory<IDuplexSessionChannel>; 
 
                         // 完成异步操作，以打开信道工厂 
                        factory.EndOpen(result); 
 
                         // 在信道工厂上根据指定的地址创建信道 
                        IDuplexSessionChannel channel = 
                                factory.CreateChannel( new EndpointAddress( "http://localhost:3036/DuplexService.svc")); 
 
                        // 打开信道 
                        IAsyncResult channelOpenResult = 
                                channel.BeginOpen(new AsyncCallback(OnOpenCompleteChannel), channel); 
 
                        if (channelOpenResult.CompletedSynchronously) 
                        { 
                                // 如果信道被打开的这个 异步操作 已经被 同步完成 则执行下一步 
                                CompleteOpenChannel(channelOpenResult); 
                        } 
                } 
 
                void OnOpenCompleteChannel(IAsyncResult result) 
                { 
                        // 该异步操作已被同步完成的话则不做任何操作，反之则执行下一步 
                        if (result.CompletedSynchronously) 
                                return; 
                        else 
                                CompleteOpenChannel(result); 
                } 
 
                void CompleteOpenChannel(IAsyncResult result) 
                { 
                        IDuplexSessionChannel channel = result.AsyncState as IDuplexSessionChannel; 
 
                        // 完成异步操作，以打开信道 
                        channel.EndOpen(result); 
 
                        // 构造需要发送到服务端的 System.ServiceModel.Channels.Message （客户端终结点与服务端终结点之间的通信单元） 
                        Message message = Message.CreateMessage( 
                                channel.GetProperty<MessageVersion>(), // MessageVersion.Soap11 （Duplex 服务仅支持 Soap11） 
                                "Silverlight20/IDuplexService/SendStockCode", // Action 为请求的目的地（需要执行的某行为的路径） 
                                txtStockCode.Text); 
 
                        // 向目的地发送消息 
                        IAsyncResult resultChannel = 
                                channel.BeginSend(message, new AsyncCallback(OnSend), channel); 
 
                        if (resultChannel.CompletedSynchronously) 
                        { 
                                // 如果向目的地发送消息的这个 异步操作 已经被 同步完成 则执行下一步 
                                CompleteOnSend(resultChannel); 
                        } 
 
                        // 监听指定的信道，用于接收返回的消息 
                        ReceiveLoop(channel); 
                } 
 
                void OnSend(IAsyncResult result) 
                { 
                        // 该异步操作已被同步完成的话则不做任何操作，反之则执行下一步 
                        if (result.CompletedSynchronously) 
                                return; 
                        else 
                                CompleteOnSend(result); 
                } 
 
                void CompleteOnSend(IAsyncResult result) 
                { 
                        try 
                        { 
                                IDuplexSessionChannel channel = (IDuplexSessionChannel)result.AsyncState; 
 
                                // 完成异步操作，以完成向目的地发送消息的操作 
                                channel.EndSend(result); 
                        } 
                        catch (Exception ex) 
                        { 
                                _syncContext.Post(WriteText, ex.ToString() + Environment.NewLine); 
                        } 
                } 
 
                void ReceiveLoop(IDuplexSessionChannel channel) 
                { 
                        // 监听指定的信道，用于接收返回的消息 
                        IAsyncResult result =    
                                channel.BeginReceive(new AsyncCallback(OnReceiveComplete), channel); 
 
                        if (result.CompletedSynchronously) 
                        { 
                                CompleteReceive(result); 
                        } 
                } 
 
                void OnReceiveComplete(IAsyncResult result) 
                { 
                        if (result.CompletedSynchronously) 
                                return; 
                        else 
                                CompleteReceive(result); 
                } 
 
                void CompleteReceive(IAsyncResult result) 
                { 
                        IDuplexSessionChannel channel = (IDuplexSessionChannel)result.AsyncState; 
 
                        try 
                        { 
                                // 完成异步操作，以接收到服务端发过来的消息 
                                Message receivedMessage = channel.EndReceive(result); 
 
                                if (receivedMessage == null) 
                                { 
                                        // 服务端会话已被关闭 
                                        // 此时应该关闭客户端会话，或向服务端发送消息以启动一个新的会话 
                                } 
                                else 
                                { 
                                        // 将接收到的信息输出到界面上 
                                        string text = receivedMessage.GetBody<string>(); 
                                        _syncContext.Post(WriteText, text + Environment.NewLine); 
 
                                        if (!_status) 
                                        { 
                                                // 关闭信道 
                                                IAsyncResult resultFactory = 
                                                        channel.BeginClose(new AsyncCallback(OnCloseChannel), channel); 
 
                                                if (resultFactory.CompletedSynchronously) 
                                                { 
                                                        CompleteCloseChannel(result); 
                                                } 
 
                                        } 
                                        else 
                                        { 
                                                // 继续监听指定的信道，用于接收返回的消息 
                                                ReceiveLoop(channel); 
                                        } 
                                } 
                        } 
                        catch (Exception ex) 
                        { 
                                // 出错则记日志 
                                using (StreamWriter sw = new StreamWriter(@"C:\Silverlight_Duplex_Log.txt", true)) 
                                { 
                                        sw.Write(ex.ToString()); 
                                        sw.WriteLine(); 
                                } 
                        } 
                } 
 
                void OnCloseChannel(IAsyncResult result) 
                { 
                        if (result.CompletedSynchronously) 
                                return; 
                        else 
                                CompleteCloseChannel(result); 
                } 
 
                void CompleteCloseChannel(IAsyncResult result) 
                { 
                        IDuplexSessionChannel channel = (IDuplexSessionChannel)result.AsyncState; 
 
                        // 完成异步操作，以关闭信道 
                        channel.EndClose(result); 
                } 
 
                void WriteText(object text) 
                { 
                        // 将信息打到界面上 
                        lblStockMessage.Text += (string)text; 
                } 
        } 
}