Chaining WCF Async Methods in Silverlight

Chaining WCF Async Methods in Silverlight

I'm developing a silverlight application and consuming WCF service with Async methods. But I couldnt make it working.

In my page I have the code below. Basically I want to first call LoginAsync then GetTablesAsync then GetPlayersAsync and meanwhile I need to call the client notify methods as well. How can I arrange it ? With Locks or is there a method for chaining these events to make sure that they will do fine?

public partial class Root : UserControl {     private object syncRoot = new object();     ServiceClient client;      ObservableCollection<Table> Tables { get; set; }     ObservableCollection<Player> Players { get; set; }     public Root()     {         InitializeComponent();          Tables = new ObservableCollection<Table>();          txtLogs.Text += "\n";          client = Helpers.GetServiceClient();          client.NotifyReceived += new EventHandler<NotifyReceivedEventArgs>(client_NotifyReceived);          client.PublishCompleted += new EventHandler<AsyncCompletedEventArgs>(client_PublishCompleted);         client.SubscribeCompleted += new EventHandler<AsyncCompletedEventArgs>(client_SubscribeCompleted);         client.GetTableListCompleted += client_GetPokerTablesCompleted;            this.Loaded += Root_Loaded;     }      void Root_Loaded(object sender, RoutedEventArgs e)     {         NewUser newUser = new NewUser();         newUser.Closed += newUser_Closed;         newUser.Show();     }      void newUser_Closed(object sender, EventArgs e)     {         NewUser n = sender as NewUser;         player = new Player         {             PlayerName = n.txtPlayerName.Text,         };          lock (syncRoot)         {              try             {                 client.GetTableListAsync();             }             catch (TimeoutException ex)             {              }             catch (CommunicationException ex)             {              }         }           lock (syncRoot)         {             client.LoginCompleted += client_LoginCompleted;             client.LoginAsync(player.PlayerName);             // publish player logged in             client.PublishAsync(String.Format("{0} is logged in", player.PlayerName));         }       } 

Answers & Comments...

Answer: 1

Do you mean you want to call them one after another? You could call the second one from the Login completed handler (then the third from the handler for the second one completing etc).

by : Peter William Donganhttp://stackoverflow.com/users/1658168

Answer: 2

I have found AsyncCTP most useful for the scenario you described. However, you can achieve roughly the same readability as roughly javascript libraries if you use the following pattern:

NewUser newUser = new NewUser(); newUser.Show(); newUser.Closed += (object sender, EventArgs e) => {     player = new Player     {         PlayerName = newUser.txtPlayerName.Text,     };      // you aren't going to be able to catch timeout     // errors in async method calls     client.GetTableListAsync();      // we can initiate login even if TableList isn't loaded yet     client.LoginAsync(player.PlayerName);     client.LoginCompleted += (s2, e2) => {         // publish player logged in         client.PublishAsync(String.Format("{0} is logged in", player.PlayerName));     } } 

by : Chui Teyhttp://stackoverflow.com/users/34461

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