1. Create an EndpointAddress instance for the base address of the service you are going to call and then create an WCF Client object.

   Visual Basic

   ' Step 1: Create an endpoint address and an instance of the WCF Client.
   Dim epAddress As New EndpointAddress("http://localhost:8000/ServiceModelSamples/Service/CalculatorService")
   Dim Client As New CalculatorClient(New WSHttpBinding(), epAddress)
   

2. Call the client operations from within the Client.

   Visual Basic

   '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)
   

3. Call Close on the WCF client and wait until the user presses the enter key to terminate the application.

   Visual Basic

   ' Step 3: Closing the client gracefully closes the connection and cleans up resources.
   Client.Close()
   
   Console.WriteLine()
   Console.WriteLine("Press <ENTER> to terminate client.")
   Console.ReadLine()
   

The following example shows you how to create a WCF client, how to call the operations of the client, and how to close the client once the operation call is completed.

Compile the generated WCF client and the following code example into an executable named Client.exe. Be sure to reference System.ServiceModel when compiling the code.

Imports System
Imports System.Collections.Generic
Imports System.Text
Imports System.ServiceModel


Module Client

    Sub Main()
        ' Step 1: Create an endpoint address and an instance of the WCF Client.
        Dim epAddress As New EndpointAddress("http://localhost:8000/ServiceModelSamples/Service/CalculatorService")
        Dim Client As New CalculatorClient(New WSHttpBinding(), epAddress)

        '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: Closing the client gracefully closes the connection and cleans up resources.
        Client.Close()

        Console.WriteLine()
        Console.WriteLine("Press <ENTER> to terminate client.")
        Console.ReadLine()

    End Sub
End Module

Ensure the service is running before attempting to use the client. For more information, see How to: Host and Run a Basic Windows Communication Foundation Service.

To launch the client, start a Windows SDK console session by selecting CMD Shell under the Microsoft Windows SDK entry in the Start menu. Navigate to the C:\Users\<user name>\Documents\Visual Studio 2005\Projects\Service\Client\bin\Debug directory, and type client and press ENTER. The operation requests and responses appear in the client console window as follows.

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 client.

If you see this output, you have successfully completed the tutorial. This sample demonstrates how to configure the WCF client in code. For troubleshooting information, see Troubleshooting the Getting Started Tutorial.

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