summary> / / / Implements the chat service interface. / / / < / summary> [ ServiceBehavior (InstanceContextMode = InstanceContextMode .Single, ConcurrencyMode = ConcurrencyMode .Multiple)] public
class ChatService : IChatService { private readonly Dictionary < Guid , IChatServiceCallback > clients = new Dictionary < Guid , IChatServiceCallback > (); #region IChatService Guid the server / / can't connect to the client. It might be because of a network / /
error, or the client was closed prematurely due to an exception or / / and was unable to disconnectedClientGuids.Add(client.Key); } } foreach ( Guid clientGuid in disconnectedClientGuids) { clients.Remove(clientGuid); } } } ); } } Notice that the
class is adorned with the following attribute. [ ServiceBehavior (InstanceContextMode = InstanceContextMode .Single, ConcurrencyMode = ConcurrencyMode .Multiple)] There are The following code listing shows the implementation. / / / <summary> / / / Implementation of the callback contract. / / / < / summary> public
class ChatServiceCallback : IChatServiceCallback { public event ClientNotifiedEventHandler ClientNotified; / / / <summary> / / / Notifies the client of the message by raising message)); } } } public delegate void ClientNotifiedEventHandler ( object sender, ClientNotifiedEventArgs e); / / / <summary> / / / Custom event arguments. / / / < / summary> public
class ClientNotifiedEventArgs : EventArgs { private readonly string message; / / / <summary> / / / Constructor. / / / < / summary> / / / <param name = "message"> Message from server The following shows the MainWindow code. / / / <summary> / / / Interaction logic for MainWindow.xaml / / / < / summary> public partial
class MainWindow : Window { private Guid clientId; private ChatServiceClient chatServiceClient; private InstanceContext instanceContext; / / / <summary> / / / Constructor. / / / < / summary> public Ignored. < / param> private void Btn_Click( object sender, RoutedEventArgs e) { string message = messageTbx.Text; if (! string .
IsNullOrEmpty(message)) { try { if (chatServiceClient.State = = CommunicationState .Faulted) { chatServiceClient.Abort(); chatServiceClient = new ChatServiceClient (instanceContext); } chatServiceClient.SendMessage the message from the server. < / param> private void ChatServiceCallback_ClientNotified( object sender, ClientNotifiedEventArgs e) { if (! string .
IsNullOrEmpty(conferenceTbx.Text)) { conferenceTbx.Text + = " \ n" ; } conferenceTbx.Text + = e.Message; } } When the window is loaded, the