Tutorial: Use a Windows Communication Foundation client

Article
05/02/2023

This tutorial describes the last of five tasks required to create a basic Windows Communication Foundation (WCF) application. For an overview of the tutorials, see Tutorial: Get started with Windows Communication Foundation applications.

After you've created and configured a Windows Communication Foundation (WCF) proxy, you create a client instance and compile the client application. You then use it to communicate with the WCF service.

In this tutorial, you learn how to:

Add code to use the WCF client.
Test the WCF client.

Add code to use the WCF client

The client code does the following steps:

Instantiates the WCF client.
Calls the service operations from the generated proxy.
Closes the client after the operation call is completed.

Open the Program.cs or Module1.vb file from the GettingStartedClient project and replace its code with the following code:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using GettingStartedClient.ServiceReference1;

namespace GettingStartedClient
{
    class Program
    {
        static void Main(string[] args)
        {
            //Step 1: Create an instance of the WCF proxy.
            CalculatorClient client = new CalculatorClient();

            // Step 2: Call the service operations.
            // Call the Add service operation.
            double value1 = 100.00D;
            double value2 = 15.99D;
            double result = client.Add(value1, value2);
            Console.WriteLine("Add({0},{1}) = {2}", value1, value2, result);

            // Call the Subtract service operation.
            value1 = 145.00D;
            value2 = 76.54D;
            result = client.Subtract(value1, value2);
            Console.WriteLine("Subtract({0},{1}) = {2}", value1, value2, result);

            // Call the Multiply service operation.
            value1 = 9.00D;
            value2 = 81.25D;
            result = client.Multiply(value1, value2);
            Console.WriteLine("Multiply({0},{1}) = {2}", value1, value2, result);

            // Call the Divide service operation.
            value1 = 22.00D;
            value2 = 7.00D;
            result = client.Divide(value1, value2);
            Console.WriteLine("Divide({0},{1}) = {2}", value1, value2, result);

            // Step 3: Close the client to gracefully close the connection and clean up resources.
            Console.WriteLine("\nPress <Enter> to terminate the client.");
            Console.ReadLine();
            client.Close();
        }
    }
}

Imports System.Collections.Generic
Imports System.Text
Imports System.ServiceModel
Imports GettingStartedClient.ServiceReference1

Module Module1

    Sub Main()
        ' Step 1: Create an instance of the WCF proxy.
        Dim Client As New CalculatorClient()

        ' Step 2: Call the service operations.
        ' Call the Add service operation.
        Dim value1 As Double = 100D
        Dim value2 As Double = 15.99D
        Dim result As Double = Client.Add(value1, value2)
        Console.WriteLine("Add({0},{1}) = {2}", value1, value2, result)

        ' Call the Subtract service operation.
        value1 = 145D
        value2 = 76.54D
        result = Client.Subtract(value1, value2)
        Console.WriteLine("Subtract({0},{1}) = {2}", value1, value2, result)

        ' Call the Multiply service operation.
        value1 = 9D
        value2 = 81.25D
        result = Client.Multiply(value1, value2)
        Console.WriteLine("Multiply({0},{1}) = {2}", value1, value2, result)

        ' Call the Divide service operation.
        value1 = 22D
        value2 = 7D
        result = Client.Divide(value1, value2)
        Console.WriteLine("Divide({0},{1}) = {2}", value1, value2, result)

        ' Step 3: Close the client to gracefully close the connection and clean up resources.
        Console.WriteLine()
        Console.WriteLine("Press <Enter> to terminate the client.")
        Console.ReadLine()
        Client.Close()

    End Sub

End Module

Notice the using (for Visual C#) or Imports (for Visual Basic) statement that imports GettingStartedClient.ServiceReference1. This statement imports the code that Visual Studio generated with the Add Service Reference function. The code instantiates the WCF proxy and calls each of the service operations that the calculator service exposes. It then closes the proxy and ends the program.

Test the WCF client

Test the application from Visual Studio

Save and build the solution.
Select the GettingStartedClient folder, and then select Set as Startup Project from the shortcut menu.
From Startup Projects, select GettingStartedClient from the drop-down list, then select Run or press F5.

Test the application from a command prompt

Open a command prompt as an administrator, and then navigate to your Visual Studio solution directory.
To start the service: Enter GettingStartedHost\bin\Debug\GettingStartedHost.exe.

To start the client: Open another command prompt, navigate to your Visual Studio solution directory, then enter GettingStartedClient\bin\Debug\GettingStartedClient.exe.

GettingStartedHost.exe produces the following output:

The service is ready.
Press <Enter> to terminate the service.

Received Add(100,15.99)
Return: 115.99
Received Subtract(145,76.54)
Return: 68.46
Received Multiply(9,81.25)
Return: 731.25
Received Divide(22,7)
Return: 3.14285714285714

GettingStartedClient.exe produces the following output:

Add(100,15.99) = 115.99
Subtract(145,76.54) = 68.46
Multiply(9,81.25) = 731.25
Divide(22,7) = 3.14285714285714

Press <Enter> to terminate the client.

Next steps

You've now completed all the tasks in the WCF get started tutorial. In this tutorial, you learned how to: