* WCF : Developing a basic WCF Client and Service

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• Create a blank solution in VS 2005. To get better understanding of code we will not use WCF project templates installed with WCF sdk.
• Add a class library
• Add reference to System.ServiceModel assembly and namespace.
• Create interface .. apply attributes

namespace MathUtility
{
    [ServiceContract]
    public interface IMath
    {
        [OperationContract]
        int AddNumbers(int x, int y);
        [OperationContract]
        int SubstractNumbers(int from, int number);
    }
}

• Create Service Class from interface. Implement Interface.

namespace MathUtility
{
    public class MathService : IMath
    {
        public int AddNumbers(int x, int y)
        {
            return (x + y);
        }

        public int SubstractNumbers(int from , int number)
        {
            return (from - number);
        }
    }
}

• Now we need to host this as a service. We will host in a console application.
  
• Add a console application project. Add Application Configuration file to the project.
  
• Add Reference to System.ServiceModel.
  
• Modify the app.config file as following.

<configuration>
<!-- This Section is exclusive for WCF configuration for both service and client -->
  <system.serviceModel>
    <!-- This section is to declare services hosted using this cofig file -->
    <services>
      <!-- This section declares individual service. name=type name which implements service contract -->
      <!-- behaviorConfiguration = name of bahavior config which we will define later -->
      <service name="MathUtility.MathService" behaviorConfiguration="MathServiceBehavior">
        <host>
          <!-- base address of the hosted service to which clients will connect-->
          <baseAddresses>
            <add baseAddress="http://MyMachine:8080/WCFServices/MathService" />
          </baseAddresses>
        </host>
        <!-- the actual address where service is exposed -->
        <endpoint address="" binding="wsHttpBinding" contract="MathUtility.IMath"></endpoint>
        <!-- The address where metadata is exposed and will be used by Svcutil.exe to generate client classes -->
        <endpoint address="mex" binding="mexHttpBinding" contract="IMetadataExchange"></endpoint>
      </service>
    </services>
    <behaviors>
      <serviceBehaviors>
        <!-- The behavior which we mentioned above in <service> section-->
        <behavior name="MathServiceBehavior">
          <!-- Exposing metadata on http. Not mandatory for fuctioning of service if client already has metadata-->
          <serviceMetadata httpGetEnabled="True"/>
        </behavior>
      </serviceBehaviors>      
    </behaviors>
  </system.serviceModel>
</configuration>

• Change host app as following.

namespace MathServiceHost
{
    class Program
    {
        static void Main(string[] args)
        {
            try
            {
                ServiceHost serviceHost = new ServiceHost(typeof(MathService));
                serviceHost.Open();
                Console.WriteLine("The Math Service is running");
                Console.WriteLine("Press <ENTER> to stop the service.");
                Console.ReadLine();
                serviceHost.Close();
            }
            catch (System.Exception ex)
            {
                Console.WriteLine(ex.Message);
                Console.WriteLine(ex.StackTrace);
            }
        }
    }
}

• Start the service.
  
• Use Svcutil.exe to generate the client classes and app.config file.

>svcutil /language:C# /config:app.config http://MyMachine:8080/WCFServices/MathService/mex

• Create a new console project. add generated .cs and app.config.
  
• add reference to System.ServiceModel and give namespace to generated .cs file
  
• You may have to remove identity tag from client config file if it has been generated. We will cover the reasons later.
  
• Use the generated classes as follows :

namespace MathClient
{
    class Program
    {
        static void Main(string[] args)
        {
            try
            {
                MathClient mathClient = new MathClient();
                Console.WriteLine(mathClient.AddNumbers(1, 1));
            }
            catch (System.Exception ex)
            {
                Console.WriteLine(ex.Message);
                Console.WriteLine(ex.InnerException.Message);
            }
        }
    }
}

• Pls leave a comment to this post if you face any issue in executing the above tutorial.

Next Post ->> Tool : WCF Configuration Editor ( SvcConfigEditor.exe)