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6. 6 [ServiceContract] public interface IJokeOfTheDayService { [OperationContract] string GetJoke(int jokeStrength); }

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8. 8 public class JokeOfTheDayService : IJokeOfTheDayService { public string GetJoke(int jokeStrength) { string result = "Invalid strength"; switch (jokeStrength) { case 0: result = "Joke 0 text"; break; case 1: result = "Joke 1 text"; break; case 2: result = "Joke 2 text"; break; } return result; } }

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14. 14 JokeOfTheDayService.JokeOfTheDayServiceClient jokeService; // Constructor public MainPage() { InitializeComponent(); jokeService = new JokeOfTheDayService.JokeOfTheDayServiceClient(); jokeService.GetJokeCompleted += new EventHandler<JokeOfTheDayService. GetJokeCompletedEventArgs> (jokeService_GetJokeCompleted); }

15. 15 JokeOfTheDayService.JokeOfTheDayServiceClient jokeService; // Constructor public MainPage() { InitializeComponent(); jokeService = new JokeOfTheDayService.JokeOfTheDayServiceClient(); jokeService.GetJokeCompleted += new EventHandler<JokeOfTheDayService. GetJokeCompletedEventArgs> (jokeService_GetJokeCompleted); }

16. 16 JokeOfTheDayService.JokeOfTheDayServiceClient jokeService; // Constructor public MainPage() { InitializeComponent(); jokeService = new JokeOfTheDayService.JokeOfTheDayServiceClient(); jokeService.GetJokeCompleted += new EventHandler<JokeOfTheDayService. GetJokeCompletedEventArgs> (jokeService_GetJokeCompleted); }

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18. 18 void jokeService_GetJokeCompleted(object sender, JokeOfTheDayService.GetJokeCompletedEventArgs e) { if (!e.Cancelled) { jokeTextBlock.Text = e.Result; } }

19. 19 private void getJokeButton_Click(object sender, RoutedEventArgs e) { int strength = 0; if (int.TryParse(strengthTextBox.Text, out strength)) { jokeService.GetJokeAsync(strength); } }

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