底层连接已关闭：receive-WCF发生意外错误

Question

我在客户端有一个Winforms C＃应用程序，它与WCF服务通信以从DB获取数据。 DB使用LINQ TO SQL类在WCF上实现。 问题是我已成功将数据提取到客户端应用程序，但在一个地方我得到以下异常：

System.Net.WebException: The underlying connection was closed: An unexpected
error occurred on a receive. ---> System.IO.IOException: Unable to read data
from the transport connection: An existing connection was forcibly closed by
the remote host. ---> System.Net.Sockets.SocketException: An existing
connection was forcibly closed by the remote host
  at System.Net.Sockets.Socket.Receive(Byte[] buffer, Int32 offset, Int32
  size, SocketFlags socketFlags)
  at System.Net.Sockets.NetworkStream.Read(Byte[] buffer, Int32 offset,
  Int32 size)
  --- End of inner exception stack trace ---
  at System.Net.Sockets.NetworkStream.Read(Byte[] buffer, Int32 offset,
  Int32 size)
  at System.Net.PooledStream.Read(Byte[] buffer, Int32 offset, Int32 size)
  at System.Net.Connection.SyncRead(HttpWebRequest request, Boolean
  userRetrievedStream, Boolean probeRead)
  --- End of inner exception stack trace ---
  at System.Net.HttpWebRequest.GetResponse()
  at System.ServiceModel.Channels.HttpChannelFactory`1.HttpRequestChannel.HttpChannel
  Request.WaitForReply(TimeSpan timeout)   An error occurred while receiving
  the HTTP response to http://localhost:13121/AttendanceService.svc. This
  could be due to the service endpoint binding not using the HTTP protocol.
  This could also be due to an HTTP request context being aborted by the
  server (possibly due to the service shutting down). See server logs for
  more details.  System.Collections.ListDictionaryInternal

客户代码：

    private void UpdateDataGrid2()
    {
        using (AttendanceServiceClient client = new AttendanceServiceClient())
        {
            try
            {
                if (client.GetAllFaculty() != null)
                {
                    allFaculty = client.GetAllFaculty().ToList<FacultyTable>();
                }
            }
            catch (System.ServiceModel.CommunicationException ce)
            {
                MessageBox.Show(ce.InnerException + "   " + ce.Message + "  " + ce.Data);
            }
        }
        var bindingList = new BindingList<FacultyTable>(allFaculty);
        var source = new BindingSource(bindingList, null);
        dataGridView2.DataSource = source;
        dataGridView2.ReadOnly = true;
        dataGridView2.Columns[2].Visible = false;
    }

WCF代码：

    public List<FacultyTable> GetAllFaculty()
    {
        using (AttendanceDataContext db = new AttendanceDataContext())
        {
            var exists = from x in db.FacultyTables
                         select x;

                return exists.ToList<FacultyTable>();
        }
    }

来自＆＃34; .svclog＆＃34;的痕迹从WCF生成的文件说：

<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="2015-03-19T14:12:20.6344448Z" /><Source Name="System.ServiceModel" /><Correlation ActivityID="{639f5dfd-953b-4437-a479-72c96a96b955}" /><Execution ProcessName="iisexpress" ProcessID="5180" ThreadID="12" /><Channel /><Computer>AHMED-PC</Computer></System><ApplicationData><TraceData><DataItem><TraceRecord xmlns="http://schemas.microsoft.com/2004/10/E2ETraceEvent/TraceRecord" Severity="Error"><TraceIdentifier>http://msdn.microsoft.com/en-US/library/System.ServiceModel.ServiceOperationExceptionOnReply.aspx</TraceIdentifier><Description>Replying to an operation threw a exception.</Description><AppDomain>/LM/W3SVC/2029513164/ROOT-1-130712479142359422</AppDomain><Source>System.ServiceModel.Dispatcher.ImmutableDispatchRuntime/1177678</Source><Exception><ExceptionType>System.ObjectDisposedException, mscorlib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089</ExceptionType><Message>Cannot access a disposed object.
Object name: 'DataContext accessed after Dispose.'.</Message><StackTrace>   at System.Data.Linq.DataContext.GetTable(Type type)
   at System.Data.Linq.CommonDataServices.GetDataMemberQuery(MetaDataMember member, Expression[] keyValues)
   at System.Data.Linq.CommonDataServices.DeferredSourceFactory`1.ExecuteKeyQuery(Object[] keyValues)
   at System.Data.Linq.CommonDataServices.DeferredSourceFactory`1.Execute(Object instance)
   at System.Data.Linq.CommonDataServices.DeferredSourceFactory`1.DeferredSource.GetEnumerator()
   at System.Data.Linq.EntitySet`1.Load()
   at System.Data.Linq.EntitySet`1.get_Count()
   at WriteArrayOfSectionTableToXml(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 WriteFacultyTableToXml(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 WriteArrayOfFacultyTableToXml(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, Boolean shouldRecycleBuffer)
   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)</StackTrace><ExceptionString>System.ObjectDisposedException: Cannot access a disposed object.
Object name: 'DataContext accessed after Dispose.'.
   at System.Data.Linq.DataContext.GetTable(Type type)
   at System.Data.Linq.CommonDataServices.GetDataMemberQuery(MetaDataMember member, Expression[] keyValues)
   at System.Data.Linq.CommonDataServices.DeferredSourceFactory`1.ExecuteKeyQuery(Object[] keyValues)
   at System.Data.Linq.CommonDataServices.DeferredSourceFactory`1.Execute(Object instance)
   at System.Data.Linq.CommonDataServices.DeferredSourceFactory`1.DeferredSource.GetEnumerator()
   at System.Data.Linq.EntitySet`1.Load()
   at System.Data.Linq.EntitySet`1.get_Count()
   at WriteArrayOfSectionTableToXml(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 WriteFacultyTableToXml(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 WriteArrayOfFacultyTableToXml(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, Boolean shouldRecycleBuffer)
   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>