What is the standardized way to pass complex types in WCF?

Question

I am a newbie in WCF, currently I am developing a TCP WCF service and I am not sure that I understand passing parameters correctly or not so I recommend you to comment and give a standardized way.

To get things clear I developed a small service for testing purpose that has single method and depends on an external .Net dll that exposes single class. The service contract code

    [ServiceContract]
    public  interface IMyService
    {
        [OperationContract]
        int Test1(actionType at, calculationType ct, action a);
        [OperationContract]
        int Test2(DataSeries s);
    }

Where actionType,calculationType,action are enums declared inside the the external dll and DataSeries is a class declared inside the dll.

The origianl defination for the DataSeries class in the dll is marked by [Serializable] only and no [DataMember] on its members.

I am using the 3rd dll on the client and server side, my surprise was both applications working fine without putting [DataContract] on the DataSeries class and without using any of [EnumMember] inside enums, [DataMember] inside class.

So what is going on?

Another Experiment:

Removing the 3rd party from the client side and using the service as it is I found that the vs2008 generates the enums and the DataSeries class and markes them with the proper attributes? like

    [System.CodeDom.Compiler.GeneratedCodeAttribute      ("System.Runtime.Serialization", "3.0.0.0")]
    [System.Runtime.Serialization.DataContractAttribute(Name="actionType",  Namespace="http://schemas.datacontract.org/2004/07/DBInterface")]
    public enum actionType : int {

        [System.Runtime.Serialization.EnumMemberAttribute()]
        All = 0,

        [System.Runtime.Serialization.EnumMemberAttribute()]
        Buy = 1,

        [System.Runtime.Serialization.EnumMemberAttribute()]
        Sell = 2,
    }

Answer 1

DataContract, DataMember and EnumMember attributes are used by the DataContractSerializer (usually basicHttpBinding or wsHttpBinding). If you are exposing an endpoint with TCP binding (netTcpBinding) only SerializableAttribute is required. Note that with DataContractSerializer you could only add SerializableAttribute to your classes and it will automatically serialize all fields.

I would recommend you the following: if you want your service to be interoperable, use basicHttpBinding and mark your classes with DataContract and DataMember attributes. If your client is a .NET application, use netTcpBinding and mark your classes with SerializableAttribute.

You could also read this post for comparison between different bindings.