無法序列化會話狀態

無法序列化會話狀態。在「StateServer」和「SQLServer」模式下，ASP.NET將序列化會話狀態對象，結果不允許不可序列化的對象或MarshalByRef對象爲。如果類似序列化由自定義會話狀態存儲以「自定義」模式完成，則適用相同的限制。無法序列化會話狀態

Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.

Exception Details: System.Web.HttpException: Unable to serialize the session state. In 'StateServer' and 'SQLServer' mode, ASP.NET will serialize the session state objects, and as a result non-serializable objects or MarshalByRef objects are not permitted. The same restriction applies if similar serialization is done by the custom session state store in 'Custom' mode.

Source Error:

An unhandled exception was generated during the execution of the current web request. Information regarding the origin and location of the exception can be identified using the exception stack trace below.

Stack Trace:

[SerializationException: Type 'Examination' in Assembly 'App_Code.aw9uvznn, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null' is not marked as serializable.]
System.Runtime.Serialization.FormatterServices.InternalGetSerializableMembers(RuntimeType type) +7735723
System.Runtime.Serialization.FormatterServices.GetSerializableMembers(Type type, StreamingContext context) +258
System.Runtime.Serialization.Formatters.Binary.WriteObjectInfo.InitMemberInfo() +111 System.Runtime.Serialization.Formatters.Binary.WriteObjectInfo.InitSerialize(Object obj, ISurrogateSelector surrogateSelector, StreamingContext context, SerObjectInfoInit serObjectInfoInit, IFormatterConverter converter, ObjectWriter objectWriter) +161
System.Runtime.Serialization.Formatters.Binary.WriteObjectInfo.Serialize(Object obj, ISurrogateSelector surrogateSelector, StreamingContext context, SerObjectInfoInit serObjectInfoInit, IFormatterConverter converter, ObjectWriter objectWriter) +51
System.Runtime.Serialization.Formatters.Binary.ObjectWriter.Serialize(Object graph, Header[] inHeaders, __BinaryWriter serWriter, Boolean fCheck) +410 System.Runtime.Serialization.Formatters.Binary.BinaryFormatter.Serialize(Stream serializationStream, Object graph, Header[] headers, Boolean fCheck) +134 System.Web.Util.AltSerialization.WriteValueToStream(Object value, BinaryWriter writer) +1577

[HttpException (0x80004005): Unable to serialize the session state. In 'StateServer' and 'SQLServer' mode, ASP.NET will serialize the session state objects, and as a result non-serializable objects or MarshalByRef objects are not permitted. The same restriction applies if similar serialization is done by the custom session state store in 'Custom' mode.]
System.Web.Util.AltSerialization.WriteValueToStream(Object value, BinaryWriter writer) +1662
System.Web.SessionState.SessionStateItemCollection.WriteValueToStreamWithAssert(Object value, BinaryWriter writer) +34
System.Web.SessionState.SessionStateItemCollection.Serialize(BinaryWriter writer) +606
System.Web.SessionState.SessionStateUtility.Serialize(SessionStateStoreData item, Stream stream) +239
System.Web.SessionState.SessionStateUtility.SerializeStoreData(SessionStateStoreData item, Int32 initialStreamSize, Byte[]& buf, Int32& length) +72
System.Web.SessionState.OutOfProcSessionStateStore.SetAndReleaseItemExclusive(HttpContext context, String id, SessionStateStoreData item, Object lockId, Boolean newItem) +87
System.Web.SessionState.SessionStateModule.OnReleaseState(Object source, EventArgs eventArgs) +560
System.Web.SessionState.SessionStateModule.OnEndRequest(Object source, EventArgs eventArgs) +160
System.Web.SyncEventExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute() +68 System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously) +75