WCF客户端不使用Web服务中的用户定义数据类型（包括SCVTrace）

Question

As requested - here is the trace i got from SVCTraceViewer.exe

<E2ETraceEvent xmlns="http://schemas.microsoft.com/2004/06/E2ETraceEvent"><System xmlns="http://schemas.microsoft.com/2004/06/windows/eventlog/system"> <EventID>524340</EventID> <Type>3</Type><SubType Name="Error">0</SubType><Level>2</Level> <TimeCreated SystemTime="2013-11-26T01:35:30.8037467Z" /> <Source Name="System.ServiceModel" /><Correlation ActivityID="{6a4de494-31a3-49ab-935f-419911742e44}" /> <Execution ProcessName="WebDev.WebServer40" ProcessID="13564" ThreadID="13" /><Channel /><Computer>CONNOR-PC</Computer></System> <ApplicationData><TraceData><DataItem><TraceRecord xmlns="http://schemas.microsoft.com/2004/10/E2ETraceEvent/TraceRecord" Severity="Error"> <TraceIdentifier>http://msdn.microsoft.com/en-GB/library/System.ServiceModel.ServiceOperationExceptionOnReply.aspx</TraceIdentifier> <Description>Replying to an operation threw a exception.</Description><AppDomain>caf40de1-1-130299029702291231</AppDomain> <Source>System.ServiceModel.Dispatcher.ImmutableDispatchRuntime/11419366</Source><Exception> <ExceptionType>System.ObjectDisposedException, mscorlib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089</ExceptionType> <Message>The ObjectContext instance has been disposed and can no longer be used for operations that require a connection.</Message> <StackTrace> at System.Data.Objects.ObjectContext.EnsureConnection() at System.Data.Objects.ObjectQuery <E2ETraceEvent xmlns="http://schemas.microsoft.com/2004/06/E2ETraceEvent"><System xmlns="http://schemas.microsoft.com/2004/06/windows/eventlog/system"> <EventID>524340</EventID> <Type>3</Type><SubType Name="Error">0</SubType><Level>2</Level> <TimeCreated SystemTime="2013-11-26T01:35:30.8037467Z" /> <Source Name="System.ServiceModel" /><Correlation ActivityID="{6a4de494-31a3-49ab-935f-419911742e44}" /> <Execution ProcessName="WebDev.WebServer40" ProcessID="13564" ThreadID="13" /><Channel /><Computer>CONNOR-PC</Computer></System> <ApplicationData><TraceData><DataItem><TraceRecord xmlns="http://schemas.microsoft.com/2004/10/E2ETraceEvent/TraceRecord" Severity="Error"> <TraceIdentifier>http://msdn.microsoft.com/en-GB/library/System.ServiceModel.ServiceOperationExceptionOnReply.aspx</TraceIdentifier> <Description>Replying to an operation threw a exception.</Description><AppDomain>caf40de1-1-130299029702291231</AppDomain> <Source>System.ServiceModel.Dispatcher.ImmutableDispatchRuntime/11419366</Source><Exception> <ExceptionType>System.ObjectDisposedException, mscorlib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089</ExceptionType> <Message>The ObjectContext instance has been disposed and can no longer be used for operations that require a connection.</Message> <StackTrace> at System.Data.Objects.ObjectContext.EnsureConnection() at System.Data.Objects.ObjectQuery 1.GetResults(Nullable 1 forMergeOption) at System.Data.Objects.ObjectQuery 1.Execute(MergeOption mergeOption) at System.Data.Objects.DataClasses.EntityCollection 1.Load(List 1 collection, MergeOption mergeOption) at System.Data.Objects.DataClasses.EntityCollection 1.Load(MergeOption mergeOption) at System.Data.Objects.DataClasses.RelatedEnd.Load() at System.Data.Objects.DataClasses.RelatedEnd.DeferredLoad() at System.Data.Objects.DataClasses.EntityCollection 1.get_Count() at WriteArrayOfProjectToXml(XmlWriterDelegator , Object , XmlObjectSerializerWriteContext , CollectionDataContract ) at Syste m.Runtime.Serialization.CollectionDataContract.WriteXmlValue(XmlWriterDelegator xmlWriter, Object obj, XmlObjectSerializerWriteContext context) at System.Runtime.Serialization.XmlObjectSerializerWriteContext.WriteDataContractValue(DataContract dataContract, XmlWriterDelegator xmlWriter, Object obj, RuntimeTypeHandle declaredTypeHandle) at System.Runtime.Serialization.XmlObjectSerializerWriteContext.SerializeWithoutXsiType(DataContract dataContract, XmlWriterDelegator xmlWriter, Object obj, RuntimeTypeHandle declaredTypeHandle) at System.Runtime.Serialization.XmlObjectSerializerWriteContext.InternalSerialize(XmlWriterDelegator xmlWriter, Object obj, Boolean isDeclaredType, Boolean writeXsiType, Int32 declaredTypeID, RuntimeTypeHandle declaredTypeHandle) at WriteUserToXml(XmlWriterDelegator , Object , XmlObjectSerializerWriteContext , ClassDataContract ) at System.Runtime.Serialization.ClassDataContract.WriteXmlValue(XmlWriterDelegator xmlWriter, Object obj, XmlObjectSerializerWriteConte xt context) at System.Runtime.Serialization.XmlObjectSerializerWriteContext.WriteDataContractValue(DataContract dataContract, XmlWriterDelegator xmlWriter, Object obj, RuntimeTypeHandle declaredTypeHandle) at System.Runtime.Serialization.XmlObjectSerializerWriteContext.SerializeWithoutXsiType(DataContract dataContract, XmlWriterDelegator xmlWriter, Object obj, RuntimeTypeHandle declaredTypeHandle) at System.Runtime.Serialization.XmlObjectSerializerWriteContext.InternalSerialize(XmlWriterDelegator xmlWriter, Object obj, Boolean isDeclaredType, Boolean writeXsiType, Int32 declaredTypeID, RuntimeTypeHandle declaredTypeHandle) at WriteArrayOfUserToXml(XmlWriterDelegator , Object , XmlObjectSerializerWriteContext , CollectionDataContract ) at System.Runtime.Serialization.CollectionDataContract.WriteXmlValue(XmlWriterDelegator xmlWriter, Object obj, XmlObjectSerializerWriteContext context) at System.Runtime.Serialization.XmlObjectSerializerWriteContext.WriteDataContractValue(DataContract dat aContract, XmlWriterDelegator xmlWriter, Object obj, RuntimeTypeHandle declaredTypeHandle) at System.Runtime.Serialization.XmlObjectSerializerWriteContext.SerializeWithoutXsiType(DataContract dataContract, XmlWriterDelegator xmlWriter, Object obj, RuntimeTypeHandle declaredTypeHandle) at System.Runtime.Serialization.DataContractSerializer.InternalWriteObjectContent(XmlWriterDelegator writer, Object graph, DataContractResolver dataContractResolver) at System.Runtime.Serialization.DataContractSerializer.InternalWriteObject(XmlWriterDelegator writer, Object graph, DataContractResolver dataContractResolver) at System.Runtime.Serialization.XmlObjectSerializer.WriteObjectHandleExceptions(XmlWriterDelegator writer, Object graph, DataContractResolver dataContractResolver) at System.Runtime.Serialization.XmlObjectSerializer.WriteObject(XmlDictionaryWriter writer, Object graph) at System.ServiceModel.Dispatcher.DataContractSerializerOperationFormatter.SerializeParameterPart(XmlDictionaryWriter w riter, PartInfo part, Object graph) at System.ServiceModel.Dispatcher.DataContractSerializerOperationFormatter.SerializeParameter(XmlDictionaryWriter writer, PartInfo part, Object graph) at System.ServiceModel.Dispatcher.DataContractSerializerOperationFormatter.SerializeBody(XmlDictionaryWriter writer, MessageVersion version, String action, MessageDescription messageDescription, Object returnValue, Object[] parameters, Boolean isRequest) at System.ServiceModel.Dispatcher.OperationFormatter.SerializeBodyContents(XmlDictionaryWriter writer, MessageVersion version, Object[] parameters, Object returnValue, Boolean isRequest) at System.ServiceModel.Dispatcher.OperationFormatter.OperationFormatterMessage.OperationFormatterBodyWriter.OnWriteBodyContents(XmlDictionaryWriter writer) at System.ServiceModel.Channels.BodyWriterMessage.OnWriteBodyContents(XmlDictionaryWriter writer) at System.ServiceModel.Channels.Message.OnWriteMessage(XmlDictionaryWriter writer) at System.ServiceModel.Channels.Bu fferedMessageWriter.WriteMessage(Message message, BufferManager bufferManager, Int32 initialOffset, Int32 maxSizeQuota) at System.ServiceModel.Channels.TextMessageEncoderFactory.TextMessageEncoder.WriteMessage(Message message, Int32 maxMessageSize, BufferManager bufferManager, Int32 messageOffset) at System.ServiceModel.Channels.HttpOutput.SerializeBufferedMessage(Message message) at System.ServiceModel.Channels.HttpOutput.Send(TimeSpan timeout) at System.ServiceModel.Channels.HttpPipeline.EmptyHttpPipeline.SendReplyCore(Message message, TimeSpan timeout) at System.ServiceModel.Channels.HttpPipeline.EmptyHttpPipeline.SendReply(Message message, TimeSpan timeout) at System.ServiceModel.Channels.HttpRequestContext.OnReply(Message message, TimeSpan timeout) at System.ServiceModel.Activation.HostedHttpContext.OnReply(Message message, TimeSpan timeout) at System.ServiceModel.Channels.RequestContextBase.Reply(Message message, TimeSpan timeout) at System.ServiceModel.Dispatcher.ImmutableDispat chRuntime.Reply(MessageRpc& rpc)System.ObjectDisposedException: The ObjectContext instance has been disposed and can no longer be used for operations that require a connection. at System.Data.Objects.ObjectContext.EnsureConnection() at System.Data.Objects.ObjectQuery 1.GetResults(Nullable 1 forMergeOption) at System.Data.Objects.ObjectQuery 1.Execute(MergeOption mergeOption) at System.Data.Objects.DataClasses.EntityCollection 1.Load(List 1 collection, MergeOption mergeOption) at System.Data.Objects.DataClasses.EntityCollection 1.Load(MergeOption mergeOption) at System.Data.Objects.DataClasses.RelatedEnd.Load() at System.Data.Objects.DataClasses.RelatedEnd.DeferredLoad() at System.Data.Objects.DataClasses.EntityCollection 1.get_Count() at WriteArrayOfProjectToXml(XmlWriterDelegator , Object , XmlObjectSerializerWriteContext , CollectionDataContract ) at System.Runtime.Serialization.CollectionDataContract.WriteXmlValue(XmlWriterDelegator xmlWriter, Object obj, XmlObjectSerializerWriteContext context) at System.Runtime.Serialization.XmlObjectSerializerWriteContext.WriteDataContractValue(DataContract dataContract, XmlWriterDelegator xmlWriter, Object obj, RuntimeTypeHandle declaredTypeHandle) at System.Runtime.Serialization.XmlObjectSerializerWriteContext.SerializeWithoutXsiType(DataContract dataContract, XmlWriterDelegator xmlWriter, Object obj, RuntimeTypeHandle declaredTypeHandle) at System.Runtime.Serialization.XmlObjectSerializerWriteContext.InternalSerialize(XmlWriterDelegator xmlWriter, Object obj, Boolean isDeclaredType, Boolean writeXsiType, Int32 declaredTypeID, RuntimeTypeHandle declaredTypeHandle) at WriteUserToXml(XmlWriterDelegator , Object , XmlObjectSerializerWriteContext , ClassDataContract ) at System.Runtime.Serialization.ClassDataContract.WriteXmlValue(XmlWriterDelegator xmlWriter, Object obj, XmlObjectSerializerWriteContext context) at System.Runtime.Serialization.XmlObjectSerializerWriteContext.WriteDataContractValue(DataContract dataContract, XmlWriterDelegator xmlWriter, Object obj, RuntimeTypeHandle declaredTypeHandle) at System.Runtime.Serialization.XmlObjectSerializerWriteContext.SerializeWithoutXsiType(DataContract dataContract, XmlWriterDelegator xmlWriter, Object obj, RuntimeTypeHandle declaredTypeHandle) at System.Runtime.Serialization.XmlObjectSerializerWriteContext.InternalSerialize(XmlWriterDelegator xmlWriter, Object obj, Boolean isDeclaredType, Boolean writeXsiType, Int32 declaredTypeID, RuntimeTypeHandle declaredTypeHandle) at WriteArrayOfUserToXml(XmlWriterDelegator , Object , XmlObjectSerializerWriteContext , CollectionDataContract ) at System.Runtime.Serialization.CollectionDataContract.WriteXmlValue(XmlWriterDelegator xmlWriter, Object obj, XmlObjectSerializerWriteContext context) at System.Runtime.Serialization.XmlObjectSerializerWriteContext.WriteDataContractValue(DataContract dataContract, XmlWriterDelegator xmlWriter, Object obj, RuntimeTypeHandle declaredTypeHandle) at System.Runtime.Serialization.XmlObjectSerializerWriteContext.SerializeWithoutXsiType(DataContract dataContract, XmlWriterDelegator xmlWriter, Object obj, RuntimeTypeHandle declaredTypeHandle) at System.Runtime.Serialization.DataContractSerializer.InternalWriteObjectContent(XmlWriterDelegator writer, Object graph, DataContractResolver dataContractResolver) at System.Runtime.Serialization.DataContractSerializer.InternalWriteObject(XmlWriterDelegator writer, Object graph, DataContractResolver dataContractResolver) at System.Runtime.Serialization.XmlObjectSerializer.WriteObjectHandleExceptions(XmlWriterDelegator writer, Object graph, DataContractResolver dataContractResolver) at System.Runtime.Serialization.XmlObjectSerializer.WriteObject(XmlDictionaryWriter writer, Object graph) at System.ServiceModel.Dispatcher.DataContractSerializerOperationFormatter.SerializeParameterPart(XmlDictionaryWriter writer, PartInfo part, Object graph) at System.ServiceModel.Dispatcher.DataContractSerializerOperationFormatter.SerializeParameter(XmlDictionaryWriter writer, PartInfo part, Object graph) at System.ServiceModel.Dispatcher.DataContractSerializerOperationFormatter.SerializeBody(XmlDictionaryWriter writer, MessageVersion version, String action, MessageDescription messageDescription, Object returnValue, Object[] parameters, Boolean isRequest) at System.ServiceModel.Dispatcher.OperationFormatter.SerializeBodyContents(XmlDictionaryWriter writer, MessageVersion version, Object[] parameters, Object returnValue, Boolean isRequest) at System.ServiceModel.Dispatcher.OperationFormatter.OperationFormatterMessage.OperationFormatterBodyWriter.OnWriteBodyContents(XmlDictionaryWriter writer) at System.ServiceModel.Channels.BodyWriterMessage.OnWriteBodyContents(XmlDictionaryWriter writer) at System.ServiceModel.Channels.Message.OnWriteMessage(XmlDictionaryWriter writer) at System.ServiceModel.Channels.BufferedMessageWriter.WriteMessage(Message message, BufferManager bufferManager, Int32 initialOffset, Int32 maxSizeQuota) at System.ServiceModel.Channels.TextMessageEncoderFactory.TextMessageEncoder.WriteMessage(Message message, Int32 maxMessageSize, BufferManager bufferManager, Int32 messageOffset) at System.ServiceModel.Channels.HttpOutput.SerializeBufferedMessage(Message message) at System.ServiceModel.Channels.HttpOutput.Send(TimeSpan timeout) at System.ServiceModel.Channels.HttpPipeline.EmptyHttpPipeline.SendReplyCore(Message message, TimeSpan timeout) at System.ServiceModel.Channels.HttpPipeline.EmptyHttpPipeline.SendReply(Message message, TimeSpan timeout) at System.ServiceModel.Channels.HttpRequestContext.OnReply(Message message, TimeSpan timeout) at System.ServiceModel.Activation.HostedHttpContext.OnReply(Message message, TimeSpan timeout) at System.ServiceModel.Channels.RequestContextBase.Reply(Message message, TimeSpan timeout) at System.ServiceModel.Dispatcher.ImmutableDispatchRuntime.Reply(MessageRpc&amp;amp; rpc)</ExceptionString></Exception></TraceRecord></DataItem></TraceData></ApplicationData></E2ETraceEvent> 1.get_Count() at WriteArrayOfProjectToXml(XmlWriterDelegator , Object , XmlObjectSerializerWriteContext , CollectionDataContract ) at System.Runtime.Serialization.CollectionDataContract.WriteXmlValue(XmlWriterDelegator xmlWriter, Object obj, XmlObjectSerializerWriteContext context) at System.Runtime.Serialization.XmlObjectSerializerWriteContext.WriteDataContractValue(DataContract dataContract, XmlWriterDelegator xmlWriter, Object obj, RuntimeTypeHandle declaredTypeHandle) at System.Runtime.Serialization.XmlObjectSerializerWriteContext.SerializeWithoutXsiType(DataContract dataContract, XmlWriterDelegator xmlWriter, Object obj, RuntimeTypeHandle declaredTypeHandle) at System.Runtime.Serialization.XmlObjectSerializerWriteContext.InternalSerialize(XmlWriterDelegator xmlWriter, Object obj, Boolean isDeclaredType, Boolean writeXsiType, Int32 declaredTypeID, RuntimeTypeHandle declaredTypeHandle) at WriteUserToXml(XmlWriterDelegator , Object , XmlObjectSerializerWriteContext , ClassDataContract ) at System.Runtime.Serialization.ClassDataContract.WriteXmlValue(XmlWriterDelegator xmlWriter, Object obj, XmlObjectSerializerWriteContext context) at System.Runtime.Serialization.XmlObjectSerializerWriteContext.WriteDataContractValue(DataContract dataContract, XmlWriterDelegator xmlWriter, Object obj, RuntimeTypeHandle declaredTypeHandle) at System.Runtime.Serialization.XmlObjectSerializerWriteContext.SerializeWithoutXsiType(DataContract dataContract, XmlWriterDelegator xmlWriter, Object obj, RuntimeTypeHandle declaredTypeHandle) at System.Runtime.Serialization.XmlObjectSerializerWriteContext.InternalSerialize(XmlWriterDelegator xmlWriter, Object obj, Boolean isDeclaredType, Boolean writeXsiType, Int32 declaredTypeID, RuntimeTypeHandle declaredTypeHandle) at WriteArrayOfUserToXml(XmlWriterDelegator , Object , XmlObjectSerializerWriteContext , CollectionDataContract ) at System.Runtime.Serialization.CollectionDataContract.WriteXmlValue(XmlWriterDelegator xmlWriter, Object obj, XmlObjectSerializerWriteContext context) at System.Runtime.Serialization.XmlObjectSerializerWriteContext.WriteDataContractValue(DataContract dataContract, XmlWriterDelegator xmlWriter, Object obj, RuntimeTypeHandle declaredTypeHandle) at System.Runtime.Serialization.XmlObjectSerializerWriteContext.SerializeWithoutXsiType(DataContract dataContract, XmlWriterDelegator xmlWriter, Object obj, RuntimeTypeHandle declaredTypeHandle) at System.Runtime.Serialization.DataContractSerializer.InternalWriteObjectContent(XmlWriterDelegator writer, Object graph, DataContractResolver dataContractResolver) at System.Runtime.Serialization.DataContractSerializer.InternalWriteObject(XmlWriterDelegator writer, Object graph, DataContractResolver dataContractResolver) at System.Runtime.Serialization.XmlObjectSerializer.WriteObjectHandleExceptions(XmlWriterDelegator writer, Object graph, DataContractResolver dataContractResolver) at System.Runtime.Serialization.XmlObjectSerializer.WriteObject(XmlDictionaryWriter writer, Object graph) at System.ServiceModel.Dispatcher.DataContractSerializerOperationFormatter.SerializeParameterPart(XmlDictionaryWriter writer, PartInfo part, Object graph) at System.ServiceModel.Dispatcher.DataContractSerializerOperationFormatter.SerializeParameter(XmlDictionaryWriter writer, PartInfo part, Object graph) at System.ServiceModel.Dispatcher.DataContractSerializerOperationFormatter.SerializeBody(XmlDictionaryWriter writer, MessageVersion version, String action, MessageDescription messageDescription, Object returnValue, Object[] parameters, Boolean isRequest) at System.ServiceModel.Dispatcher.OperationFormatter.SerializeBodyContents(XmlDictionaryWriter writer, MessageVersion version, Object[] parameters, Object returnValue, Boolean isRequest) at System.ServiceModel.Dispatcher.OperationFormatter.OperationFormatterMessage.OperationFormatterBodyWriter.OnWriteBodyContents(XmlDictionaryWriter writer) at System.ServiceModel.Channels.BodyWriterMessage.OnWriteBodyContents(XmlDictionaryWriter writer) at System.ServiceModel.Channels.Message.OnWriteMessage(XmlDictionaryWriter writer) at System.ServiceModel.Channels.BufferedMessageWriter.WriteMessage(Message message, BufferManager bufferManager, Int32 initialOffset, Int32 maxSizeQuota) at System.ServiceModel.Channels.TextMessageEncoderFactory.TextMessageEncoder.WriteMessage(Message message, Int32 maxMessageSize, BufferManager bufferManager, Int32 messageOffset) at System.ServiceModel.Channels.HttpOutput.SerializeBufferedMessage(Message message) at System.ServiceModel.Channels.HttpOutput.Send(TimeSpan timeout) at System.ServiceModel.Channels.HttpPipeline.EmptyHttpPipeline.SendReplyCore(Message message, TimeSpan timeout) at System.ServiceModel.Channels.HttpPipeline.EmptyHttpPipeline.SendReply(Message message, TimeSpan timeout) at System.ServiceModel.Channels.HttpRequestContext.OnReply(Message message, TimeSpan timeout) at System.ServiceModel.Activation.HostedHttpContext.OnReply(Message message, TimeSpan timeout) at System.ServiceModel.Channels.RequestContextBase.Reply(Message message, TimeSpan timeout) at System.ServiceModel.Dispatcher.ImmutableDispatchRuntime.Reply(MessageRpc&amp;amp; rpc)</ExceptionString></Exception></TraceRecord></DataItem></TraceData></ApplicationData></E2ETraceEvent>

Recieving the following CommunicationException error when returning an auto generated entity class from my web service to the client

The User class is autogenerated when i import the database model, but it will not pass through the web service to the client when i call the following method.

  using (UserService1Client db = new UserService1Client()) {

             User[] newarray = db.userSearch(this.Model.Forename, 
                   this.Model.Surname, 
                   this.Model.Certifications, this.Model.UserTypes);
         kTrace); 
            }

Here's my stack trace..

A first chance exception of type 'System.ServiceModel.CommunicationException' occurred in mscorlib.dll
There was a communication problem. The underlying connection was closed: The connection was closed unexpectedly.
Server stack trace: 
   at System.ServiceModel.Channels.HttpChannelUtilities.ProcessGetResponseWebException(WebException webException, HttpWebRequest request, HttpAbortReason abortReason)
   at System.ServiceModel.Channels.HttpChannelFactory`1.HttpRequestChannel.HttpChannelRequest.WaitForReply(TimeSpan timeout)
   at System.ServiceModel.Channels.RequestChannel.Request(Message message, TimeSpan timeout)
   at System.ServiceModel.Dispatcher.RequestChannelBinder.Request(Message message, TimeSpan timeout)
   at System.ServiceModel.Channels.ServiceChannel.Call(String action, Boolean oneway, ProxyOperationRuntime operation, Object[] ins, Object[] outs, TimeSpan timeout)
   at System.ServiceModel.Channels.ServiceChannelProxy.InvokeService(IMethodCallMessage methodCall, ProxyOperationRuntime operation)
   at System.ServiceModel.Channels.ServiceChannelProxy.Invoke(IMessage message)

Exception rethrown at [0]: 
   at System.Runtime.Remoting.Proxies.RealProxy.HandleReturnMessage(IMessage reqMsg, IMessage retMsg)
   at System.Runtime.Remoting.Proxies.RealProxy.PrivateInvoke(MessageData& msgData, Int32 type)
   at SimpleMvvmWpf1.Local_DatabaseServiceCS4.IUserService1.userSearch(String Forename, String Surname, String Certifications, String UserTypes)
   at SimpleMvvmWpf1.Local_DatabaseServiceCS4.UserService1Client.userSearch(String Forename, String Surname, String Certifications, String UserTypes) in i:\TRUNK\SimpleMvvmWpf1\SimpleMvvmWpf1\Service References\Local_DatabaseServiceCS4\Reference.cs:line 1613
   at SimpleMvvmWpf1.SearchViewModel.SubmitSearch() in i:\TRUNK\SimpleMvvmWpf1\SimpleMvvmWpf1\ViewModels\SearchViewModel.cs:line 51

And my methods..

[OperationContract]
[WebGet(ResponseFormat = WebMessageFormat.Xml, UriTemplate = "GetUsers", BodyStyle = WebMessageBodyStyle.WrappedRequest)]
List<User> GetUsers();


       public List<UserProfile> GetUsers()
    {
        using (cs4_databaseEntities entities = new cs4_databaseEntities())
        {
            try
            {
                var queryResult = from i in entities.Users select i;
                List<User> uList= queryResult.ToList();
                return uList; 
            }
            catch (Exception e)
            {
                Console.WriteLine(e.Message);
                return new List<UserProfile>();
            }
        }
    }

The User Class has the [DataContractAttribute(IsReference=true)] and the variables have the [DataMemberAttribute()] however i'm still not getting anything through, i've also played about with the binding configuration setting closeTimeout="00:40:00" openTimeout="00:40:00" receiveTimeout="00:40:00" sendTimeout="00:40:00" maxBufferSize="2147483647" maxReceivedMessageSize="2147483647" maxBufferPoolSize="2147483647"

Any help would be great, this is rattLing my brain!!

Answer 1

Your code is using so called Lazy Loading which in short means that data will be actually read only on demand. This will happen during response serialization (as it is shown in the stack trace), a long after your DbContext ( cs4_databaseEntities in this case) is disposed - because it lives only within using block. The simplest solution is to disable lazy loading:

yourContext.ContextOptions.LazyLoadingEnabled = false;

Refer for example this good article about this topic.