下面我們來接著做客戶端：
1.在Solution中添加SiliverLight Project，命名為ChatClient
這里，我將對應的網站 放在WCF Service中

2.先在ChatClient工程中 添加DLL引用：
System.Runtime.Serialization.dll
System.ServiceModel.dll
System.ServiceModel.PollingDuplex.dll

3.先繪制一個簡單界面，修改Page.xaml 如下：
<UserControl?x:Class="ChatClient.Page"
????xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"?
????xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"?
????Width="655"?Height="420">
????<Grid?x:Name="LayoutRoot"
??????????Background="White"
??????????ShowGridLines="True">
????????<Grid.RowDefinitions>
????????????<RowDefinition?/>
????????????<RowDefinition?Height="40"?/>
????????</Grid.RowDefinitions>

????????<Grid?ShowGridLines="True"
??????????????Grid.Row="0">
????????????<Grid.ColumnDefinitions>
????????????????<ColumnDefinition?/>
????????????????<ColumnDefinition?Width="150"?/>
????????????</Grid.ColumnDefinitions>

????????????<!--聊天內容-->
????????????<!--TODO:加入滾動條-->
????????????<TextBlock?x:Name="txt_CharText"
???????????????????????Grid.Column="0"
???????????????????????Grid.Row="0"
???????????????????????VerticalAlignment="Center"
???????????????????????HorizontalAlignment="Center"?/>
????????????
????????????<!--用戶列表-->
????????????<!--TODO:加入滾動條?ListView-->
????????????<TextBlock?x:Name="txt_lstChatters"
???????????????????????Grid.Column="1"
???????????????????????VerticalAlignment="Top"
???????????????????????HorizontalAlignment="Center"?/>
????????</Grid>

????????<Grid?Grid.Row="1"
??????????????ShowGridLines="True">
????????????<Grid.ColumnDefinitions>
????????????????<ColumnDefinition?/>
????????????????<ColumnDefinition?Width="75"?/>
????????????????<ColumnDefinition?Width="150"?/>
????????????????<ColumnDefinition?Width="75"?/>
????????????</Grid.ColumnDefinitions>

????????????<!--輸入對話框-->
????????????<TextBox?x:Name="tb_Message"
?????????????????????Grid.Column="0"
?????????????????????Margin="5,5,5,5"
?????????????????????KeyDown="tb_Message_KeyDown"/>

????????????<!--發送按鈕-->
????????????<Button?x:Name="btn_Say"
????????????????????Grid.Column="1"
????????????????????Width="70"
????????????????????Height="30"
????????????????????HorizontalAlignment="Center"
????????????????????VerticalAlignment="Center"
????????????????????Click="btn_Say_Click">
????????????????<TextBlock?HorizontalAlignment="Center"
???????????????????????????VerticalAlignment="Center">Send</TextBlock></Button>
????????????
????????????<!--名字輸入對話框-->
????????????<TextBox?x:Name="tb_Name"
?????????????????????Grid.Column="2"
?????????????????????Margin="5,5,5,5"
?????????????????????Text="Guest"
?????????????????????KeyDown="tb_Name_KeyDown"/>
????????????

????????????<!--Connect按鈕-->
????????????<Button?x:Name="btn_Connect"
????????????????????Grid.Column="3"
????????????????????Width="70"
????????????????????Height="30"
????????????????????HorizontalAlignment="Center"
????????????????????VerticalAlignment="Center"
????????????????????Click="btn_Connect_Click">
????????????????<TextBlock?HorizontalAlignment="Center"
???????????????????????????VerticalAlignment="Center">Connect</TextBlock>
????????????</Button>

????????</Grid>
????</Grid>
</UserControl>
為了方便用戶輸入，在兩個TextBox中 加入了KeyDown事件 用來截獲"回車"符

4.在相應的 Page.xaml.cs中 添加如下引用：
using?System.ServiceModel;
using?System.ServiceModel.Channels;
using?System.Threading;
5.添加如下代碼，創建Channel
????????SynchronizationContext?uiThread;
????????IDuplexSessionChannel?m_Channel;

????????public?void?InitChannel()
????????{
????????????//?Grab?a?reference?to?the?UI?thread.
????????????uiThread?=?SynchronizationContext.Current;

????????????uiThread.Post(WriteText,?"Connecting"?+?Environment.NewLine);

????????????//?Instantiate?the?binding?and?set?the?time-outs.
????????????PollingDuplexHttpBinding?binding?=?new?PollingDuplexHttpBinding()
????????????{
????????????????PollTimeout?=?TimeSpan.FromSeconds(10),
????????????????InactivityTimeout?=?TimeSpan.FromMinutes(1)
????????????};

????????????//?Instantiate?and?open?channel?factory?from?binding.
????????????IChannelFactory<IDuplexSessionChannel>?factory?=
????????????????binding.BuildChannelFactory<IDuplexSessionChannel>(new?BindingParameterCollection());

????????????IAsyncResult?factoryOpenResult?=
????????????????factory.BeginOpen(new?AsyncCallback(OnOpenCompleteFactory),?factory);
????????????if?(factoryOpenResult.CompletedSynchronously)
????????????{
????????????????CompleteOpenFactory(factoryOpenResult);
????????????}
????????} 這里利用
SynchronizationContext.Current.Post() 異步向頁面輸送信息

6.加如相應的完成事件
void?OnOpenCompleteFactory(IAsyncResult?result)
????????{
????????????if?(result.CompletedSynchronously)
????????????????return;
????????????else
????????????????CompleteOpenFactory(result);

????????}

????????void?CompleteOpenFactory(IAsyncResult?result)
????????{
????????????IChannelFactory<IDuplexSessionChannel>?factory?=
????????????????(IChannelFactory<IDuplexSessionChannel>)result.AsyncState;

????????????factory.EndOpen(result);

????????????//?The?factory?is?now?open.?Create?and?open?a?channel?from?the?channel?factory.
????????????IDuplexSessionChannel?channel?=
????????????????factory.CreateChannel(new?EndpointAddress("http://192.168.0.13:18600/ChatService.svc"));

????????????IAsyncResult?channelOpenResult?=
????????????????channel.BeginOpen(new?AsyncCallback(OnOpenCompleteChannel),?channel);
????????????if?(channelOpenResult.CompletedSynchronously)
????????????{
????????????????CompleteOpenChannel(channelOpenResult);
????????????}
????????}

????????void?OnOpenCompleteChannel(IAsyncResult?result)
????????{
????????????if?(result.CompletedSynchronously)
????????????????return;
????????????else
????????????????CompleteOpenChannel(result);
????????}

????????void?CompleteOpenChannel(IAsyncResult?result)
????????{
????????????IDuplexSessionChannel?channel?=?(IDuplexSessionChannel)result.AsyncState;

????????????channel.EndOpen(result);

????????????this.m_Channel?=?channel;

????????????//?The?channel?is?now?open.?Send?a?message.
????????????Message?message?=?Message.CreateMessage(channel.GetProperty<MessageVersion>(),?"Silverlight/IChat/JoinChat",?this.tb_Name.Text.ToString());
????????????IAsyncResult?resultChannel?=?channel.BeginSend(message,?new?AsyncCallback(OnSend),?channel);
????????????if?(resultChannel.CompletedSynchronously)
????????????{
????????????????CompleteOnSend(resultChannel);
????????????}

????????????//?Also?start?the?receive?loop?to?listen?for?callbacks?from?the?service.
????????????ReceiveLoop(channel);
????????}

注意：
(1)這里的
IDuplexSessionChannel?channel?=
????????????????factory.CreateChannel(new?EndpointAddress("http://192.168.0.13:18600/ChatService.svc")); 這個地址應該添入，WCF Service的地址，不要忘記端口號

(2)利用
IDuplexSessionChannel.BeginSend()方法 與服務器通信

7.完成與服務器通信的相應調用
?void?OnSend(IAsyncResult?result)
????????{
????????????if?(result.CompletedSynchronously)
????????????????return;
????????????else
????????????????CompleteOnSend(result);
????????}


????????void?CompleteOnSend(IAsyncResult?result)
????????{
????????????IDuplexSessionChannel?channel?=?(IDuplexSessionChannel)result.AsyncState;

????????????channel.EndSend(result);?
????????}

????????void?ReceiveLoop(IDuplexSessionChannel?channel)
????????{
????????????//?Start?listening?for?callbacks.
????????????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)
????????{
????????????//?A?callback?was?received.
????????????IDuplexSessionChannel?channel?=?(IDuplexSessionChannel)result.AsyncState;

????????????try
????????????{
????????????????Message?receivedMessage?=?channel.EndReceive(result);

????????????????if?(receivedMessage?==?null)
????????????????{
????????????????????//?Server?closed?its?output?session,?can?close?client?channel,?
????????????????????//?or?continue?sending?messages?to?start?a?new?session.
????????????????}
????????????????else
????????????????{
????????????????????//?Show?the?service?response?in?the?UI.
????????????????????string?text?=?receivedMessage.GetBody<string>();
????????????????????uiThread.Post(WriteText,?text?+?Environment.NewLine);
????????????????????ReceiveLoop(channel);
????????????????}
????????????}
????????????catch?(CommunicationObjectFaultedException)
????????????{
????????????????//?The?channel?inactivity?time-out?was?reached.
????????????}

????????}

????????private?void?SendMessage(string?text)
????????{
????????????//?The?channel?is?now?open.?Send?a?message
????????????Message?message?=?Message.CreateMessage(this.m_Channel.GetProperty<MessageVersion>(),?"Silverlight/IChat/SayChat",?text);
????????????IAsyncResult?resultChannel?=?this.m_Channel.BeginSend(message,?new?AsyncCallback(OnSend),?this.m_Channel);
????????????if?(resultChannel.CompletedSynchronously)
????????????{
????????????????CompleteOnSend(resultChannel);
????????????}

????????????//?Also?start?the?receive?loop?to?listen?for?callbacks?from?the?service.
????????????ReceiveLoop(this.m_Channel);
????????}
8.加入前臺邏輯處理
????????private?void?btn_Say_Click(object?sender,?RoutedEventArgs?e)
????????{
????????????SendMessage(this.tb_Message.Text.ToString());
????????????this.tb_Message.Text?=?"";
????????}

????????private?void?btn_Connect_Click(object?sender,?RoutedEventArgs?e)
????????{
????????????InitChannel();
????????}

????????private?void?tb_Message_KeyDown(object?sender,?KeyEventArgs?e)
????????{
????????????if?(e.Key?==?Key.Enter)
????????????{
????????????????SendMessage(this.tb_Message.Text.ToString());
????????????????this.tb_Message.Text?=?"";
????????????}
????????}

????????private?void?tb_Name_KeyDown(object?sender,?KeyEventArgs?e)
????????{
????????????if?(e.Key?==?Key.Enter)
????????????{
????????????????InitChannel();
????????????}
????????}

????????void?WriteText(object?text)
????????{
????????????this.txt_CharText.Text?+=?(string)text;
????????}
***********************************華麗的分割線**************************************

至此 一個支持回調的SiliverLight 2.0 聊天室 就完成了，從中間可以看出，SiliverLight對WCF的支持還是不夠好，
它并不能連接TCP的WCF Service Host 這樣，它所支持的所謂CallBack實際上 是SiliverLight內部自己的輪詢，
在本質上，似乎還是沒有什么重大的突破，只是做的更有效率一點而已，但是SiliverLight所支持的多線程操作，
使其有更好的可發展空間，這一點，也是讓大家十分高興的~畢竟不會象原來那樣，因為種種原因，整個瀏覽器崩掉~

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應要求 現在補上我的Sulotion? :?? Download

轉載于:https://www.cnblogs.com/monkeyboyabc/archive/2008/07/14/1242520.html

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