WCF Serialization Error Using NetTCP - wcf

Question

Using VS2012 and NetTcpBinding. I am getting the following error when I call the serviceContract from the client - The service is hosted in IIS:
There was an error while trying to serialize parameter CS.ServiceContracts.Zzzzzz.Common:GetZipCodesResult. The InnerException message was 'Type 'System.DelegateSerializationHolder+DelegateEntry' with data contract name 'DelegateSerializationHolder.DelegateEntry:http://schemas.datacontract.org/2004/07/System' is not expected. Consider using a DataContractResolver or add any types not known statically to the list of known types - for example, by using the KnownTypeAttribute attribute or by adding them to the list of known types passed to DataContractSerializer.'. Please see InnerException for more details.
Here is my ServiceContract:
[ServiceContract(SessionMode = SessionMode.Allowed, Namespace = "CS.ServiceContracts.Zzzzzz.Common",
Name = "IZzzzzzCommonService")]
public interface IZzzzzzCommonService
{
[OperationContract]
GetZipCodesResponse GetZipCodes(GetZipCodesRequest request);
}
Here is my DataContract:
[DataContract]
[Serializable]
public class GetZipCodesResponse : ResponseBase
{
[DataMember(IsRequired = true)]
public List<ZipCodes> ZipCodes { get; set; }
}
And here is the ResponseBase:
[DataContract]
[Serializable]
[KnownType(typeof(GetZipCodesResponse)), XmlInclude(typeof(GetZipCodesResponse))]
public class ResponseBase
{
[DataMember(IsRequired = true)]
public int ResponseCode { get; set; }
[DataMember(IsRequired = false)]
public int ReasonCode { get; set; }
[DataMember(IsRequired = false)]
public string ReasonText { get; set; }
}
Here is the Implementation of the serviceContract Interface:
public class ZzzzzzCommonService : IZzzzzzCommonService
{
public GetZipCodesResponse GetZipCodes(GetZipCodesRequest request)
{
var response = new GetZipCodesResponse();
try
{
response.ZipCodes = ZipCodes.GetCustom(request.ZipCode, request.City, request.State);
}
catch (Exception ex)
{
this.BuildExceptionResponse(response, ex);
}
return response; // I get to this line ok, but here is where the error occurs
}
}
And here is the client code where I am calling the Service:
public void ZipCodes()
{
var endPoint = new EndpointAddress(
"net.tcp://localhost/CS.WebService.Zzzzzz.Common/ZzzzzzCommonService.svc");
var binding = new NetTcpBinding { TransferMode = TransferMode.Buffered, SendTimeout = TimeSpan.MaxValue, ReceiveTimeout = TimeSpan.MaxValue, MaxReceivedMessageSize = 100000000, MaxBufferSize = 100000000 };
using (var channel = new ChannelFactory<IZzzzzzCommonService>(binding, endPoint))
{
try
{
channel.Endpoint.Contract.SessionMode = SessionMode.Allowed;
var proxy = channel.CreateChannel();
var request = new GetZipCodesRequest();
request = new GetZipCodesRequest { ZipCode = "32701" };
response = proxy.GetZipCodes(request);
}
}
}
I have debugged the code and I am getting into the entity and the dataSet is populated with the appropriate rows but when it sends the dataset back is when I get the errors.
Not sure what I am missing. I believe I have the serviceContract and dataContract members decorated correctly so not sure why it is having problems serializing the List.

Answer 1

The problem was the ZipCode class. It was an Entity class and it was not able to be serialized. So I deconstructed the class and it was able to send it back to the client.