Asyncronous WCF Event on completion

Run the ServiceModel Metadata Utility Tool (Svcutil.exe) with both the /async and the /tcv:Version35 command options together as shown in the following command.

This generates, in addition to the synchronous and standard delegate-based asynchronous operations System.EventArgs types for each operation (of the form <operationName>CompletedEventArgs) for use with the event-based asynchronous calling approach.

Example of usage:

using System;

namespace Microsoft.ServiceModel.Samples
    // The service contract is defined in generatedClient.cs, generated from the service by the svcutil tool.

    class Client
        static void Main()
            Console.WriteLine(“Press <ENTER> to terminate client once the output is displayed.”);

            // Create a client
            CalculatorClient client = new CalculatorClient();

            // AddAsync
            double value1 = 100.00D;
            double value2 = 15.99D;
            client.AddCompleted += new EventHandler<AddCompletedEventArgs>(AddCallback);
            client.AddAsync(value1, value2);
            Console.WriteLine(“Add({0},{1})”, value1, value2);

            // SubtractAsync
            value1 = 145.00D;
            value2 = 76.54D;
            client.SubtractCompleted += new EventHandler<SubtractCompletedEventArgs>(SubtractCallback);
            client.SubtractAsync(value1, value2);
            Console.WriteLine(“Subtract({0},{1})”, value1, value2);

            // Multiply
            value1 = 9.00D;
            value2 = 81.25D;
            double result = client.Multiply(value1, value2);
            Console.WriteLine(“Multiply({0},{1}) = {2}”, value1, value2, result);

            // Divide
            value1 = 22.00D;
            value2 = 7.00D;
            result = client.Divide(value1, value2);
            Console.WriteLine(“Divide({0},{1}) = {2}”, value1, value2, result);


            //Closing the client gracefully closes the connection and cleans up resources

        // Asynchronous callbacks for displaying results.
        static void AddCallback(object sender, AddCompletedEventArgs e)
            Console.WriteLine(“Add Result: {0}”, e.Result);

        static void SubtractCallback(object sender, SubtractCompletedEventArgs e)
            Console.WriteLine(“Subtract Result: {0}”, e.Result);


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