WCF Contracts

3 Types of WCF Contracts:

1. Service contracts: Maps class methods to WSDL services.


2. Data contracts: Maps .NET classes to XML Schemas.


3. Message contracts: Maps .NET classes to SOAP messages

I read through the section entitled "Service Contracts" and the message exchanges described follow standard communication patterns:

• Request-Response (Synchronous and Asynchronous)


• One-way


• Duplex communication

I started working with the [DataContract] and [DataMember] attributes, which handle the manner in which model classes are mapped to the XSD ComplexType.

Very cool stuff.

Here's some sample code I wrote:

using System;
using System.ServiceModel;
using System.Runtime.Serialization;

namespace WinCommFoundation
{
    [DataContract (Namespace="http://philiptenn.com/wcf", Name="PersonComplexType")]
    public class Person
    {
        [DataMember(Name = "FirstName", Order = 1, IsRequired = true)] 
        public String FirstName;

        [DataMember(Name = "LastName", Order = 2, IsRequired = true)]
        public String LastName;

        [DataMember(Name = "ID", Order = 0, IsRequired = true)]
        public Int64 PersonId;

        [DataMember(Name = "Birthday", Order = 3, IsRequired = true)]
        public DateTime DateOfBirth;

        [DataMember(Name = "LastAccessDate", Order = 4, IsRequired = false)]
        public DateTime LastAccessed;

    }
    [ServiceContract]
    public interface IPersonService
    {
        [OperationContract]
        Person GetPerson();
    }

    public class PersonService : IPersonService
    {
        public Person GetPerson()
        {
            Person person = new Person();
            person.PersonId = 0L;
            person.FirstName = "John";
            person.LastName = "Smith";
            person.DateOfBirth = DateTime.Parse("1990-10-01");
            person.LastAccessed = DateTime.Now;
            return person;
        }
    }

    public class Service
    {
        public static void Main(string[] args)
        {
            ServiceHost serviceHost = new ServiceHost(typeof(PersonService));
            serviceHost.Open();

            Console.WriteLine("Running PersonService, hit any key to end.");
            Console.ReadLine();
            serviceHost.Close();
        }
    }
}

And here is the corresponding App.config file:

<?xml version="1.0" encoding="utf-8" ?>
<configuration>
  <system.serviceModel>
    <services>
      <service name="WinCommFoundation.PersonService" behaviorConfiguration="personServiceBehavior">
        <host>
          <baseAddresses>
            <add baseAddress="http://localhost:8000/wcfTest"/>
          </baseAddresses>
        </host>
        <endpoint address=""
                  binding="basicHttpBinding"
                  contract="WinCommFoundation.IPersonService" />
        <endpoint address="mex"
                  binding="mexHttpBinding"
                  contract="IMetadataExchange"/>
      </service>
    </services>

    <behaviors>
      <serviceBehaviors>
        <behavior name="personServiceBehavior">
          <serviceMetadata httpGetEnabled="true"/>
        </behavior>
      </serviceBehaviors>
    </behaviors>
  </system.serviceModel>
</configuration>

This created the following XSD:

<?xml version="1.0" encoding="utf-8" ?> 
<xs:schema elementFormDefault="qualified" targetNamespace="http://philiptenn.com/wcf" xmlns:xs="http://www.w3.org/2001/XMLSchema" xmlns:tns="http://philiptenn.com/wcf">
  <xs:complexType name="PersonComplexType">
    <xs:sequence> 
      <xs:element name="ID" type="xs:long" /> 
      <xs:element name="FirstName" nillable="true" type="xs:string" /> 
      <xs:element name="LastName" nillable="true" type="xs:string" /> 
      <xs:element name="Birthday" type="xs:dateTime" /> 
      <xs:element minOccurs="0" name="LastAccessDate" type="xs:dateTime" /> 
    </xs:sequence>
  </xs:complexType>
  <xs:element name="PersonComplexType" nillable="true" type="tns:PersonComplexType" /> 
</xs:schema>