MessageContract in WCF: Part 7

Before reading this article, I highly recommend reading my previous parts:

• Method overloading in WCF: Part 4
• What a DataContract and DataMember are in WCF: Part 5
• KnownType Attribute in WCF: Part 6

A MessageContract provides the full control over Soap messages. Like if you want to send some information in a Soap header then you can send it using a MessageContract. In a MessageContract you can pass the sensitive data, like user credentials, licence key and so on. You can customize the wrappername as well as remove it. In a previous part of this series we learn about DataContracts and how to control Soap messages. But in a DataControl we have limited control.

Create a WCF application and implement the following datacontract.

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

namespace MessageContractImplimentation
{
    [ServiceContract]
    public interface IService1
    {
        [OperationContract]
        string GetData(int value);

        [OperationContract]
        CompositeType GetDataUsingDataContract(CompositeType composite);

    }

    [MessageContract(IsWrapped=true,WrapperName="TestMessage",ProtectionLevel=System.Net.Security.ProtectionLevel.None,WrapperNamespace="http://localhost:8080/MessageContract")]
    public class CompositeType
    {
        [MessageHeader(Actor="Pramod",MustUnderstand=false,Name="Thakur",ProtectionLevel=System.Net.Security.ProtectionLevel.None,Relay=true)]
        public string Key { get; set; }

        [MessageHeader(Actor="Prem",MustUnderstand=true,Name="Kumar",ProtectionLevel=System.Net.Security.ProtectionLevel.None,Relay=false)]
        public string PK { get; set; }

        [MessageBodyMember(Name="Active",Order=1,ProtectionLevel=System.Net.Security.ProtectionLevel.None)]
        public bool Status { get; set; }

        [MessageBodyMember]
        public string Data { get; set; }
    }
}

Properties of MessageContract

1. IsWrapped: This property specifies whether the message body has a wrapper element.
   

   [MessageContract(IsWrapped=true)]

2. WrapperName: Using this property you can get or set the wrappername.
   

   [MessageContract(WrapperName="TestMessage")]

3. ProtectionLevel: Using this property you can specify the protection level of the message. The ProtectionLevel is an enum. You can set it either to EncryptAndSign, Sign or None.
   

   [MessageContract(ProtectionLevel=System.Net.Security.ProtectionLevel.None)]

4. WrapperNamespace: You can specify the namespace.
   

   [MessageContract(WrapperNamespace="http://localhost:8080/MessageContract")]

Attributes of MessageContract

1. MessageHeader: In this attribute we can send the sensitive data like user credentials, Key and so on.
   

   [MessageHeader(Actor="Pramod",MustUnderstand=false,Name="Thakur",ProtectionLevel=System.Net.Security.ProtectionLevel.None,Relay=true)]

2. MessageHeaderArray: Specifies that the default wrapper element in the SOAP message must not be written around array types in a header element.
   

   [MessageHeaderArray(Actor="Anuj",MustUnderstand=false,Name="AnujHeaderArray",ProtectionLevel=System.Net.Security.ProtectionLevel.None,Relay=true)]

3. MessageBodyMember: By using this we can send the any data.
   

   [MessageBodyMember(Name="Active",Order=1,ProtectionLevel=System.Net.Security.ProtectionLevel.None)]

4. MessageParameter: On the MSDN, MessageParameter controls the name of the request and response parameter names. Cannot be used with Message or message contracts.
   

   [MessageParameter(Name="MP")]

5. MessageProperty: According to the MSDN, MessageProperty represents data that is passed locally with a custom message type but not serialized into a SOAP message.
   

   [MessageProperty(Name="Prop")]

I will explain these attributes and properties in detail in a later article.

I hope you will enjoy this article.

Happy coding.