TypeLoadExceptionHolder object can be inserted during unsuccessful Bynary Deserialization

I am using Binary Serialization to save and then reload state ot the object. In my post Issues using binary serialization to store object state for unit tests I described why I have to use it and how I tried to avoid versioning problems.

I was able to read the object and access different properties of it withowt any warnings, but later, when the object was tried to be stored in Session, I've got the following error:

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. ---> System.Runtime.Serialization.SerializationException: Type 'System.Runtime.Serialization.TypeLoadExceptionHolder' in Assembly 'mscorlib, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089' is not marked as serializable.

at System.Runtime.Serialization.FormatterServices.InternalGetSerializableMembers(RuntimeType type)

at System.Runtime.Serialization.FormatterServices.GetSerializableMembers(Type type, StreamingContext context)

at System.Runtime.Serialization.Formatters.Binary.WriteObjectInfo.InitMemberInfo()

at System.Runtime.Serialization.Formatters.Binary.WriteObjectInfo.InitSerialize(Object obj, ISurrogateSelector surrogateSelector, StreamingContext context, SerObjectInfoInit serObjectInfoInit, IFormatterConverter converter, ObjectWriter objectWriter)

at System.Runtime.Serialization.Formatters.Binary.WriteObjectInfo.Serialize(Object obj, ISurrogateSelector surrogateSelector, StreamingContext context, SerObjectInfoInit serObjectInfoInit, IFormatterConverter converter, ObjectWriter objectWriter)

at System.Runtime.Serialization.Formatters.Binary.ObjectWriter.Serialize(Object graph, Header[] inHeaders, __BinaryWriter serWriter, Boolean fCheck)

at System.Runtime.Serialization.Formatters.Binary.BinaryFormatter.Serialize(Stream serializationStream, Object graph, Header[] headers, Boolean fCheck)

at System.Web.Util.AltSerialization.WriteValueToStream(Object value, BinaryWriter writer)

--- End of inner exception stack trace ---

at System.Web.Util.AltSerialization.WriteValueToStream(Object value, BinaryWriter writer)

at System.Web.SessionState.SessionStateItemCollection.WriteValueToStreamWithAssert(Object value, BinaryWriter writer)

at System.Web.SessionState.SessionStateItemCollection.Serialize(BinaryWriter writer)

at System.Web.SessionState.SessionStateUtility.Serialize(SessionStateStoreData item, Stream stream)

at System.Web.SessionState.SessionStateUtility.SerializeStoreData(SessionStateStoreData item, Int32 initialStreamSize, Byte[]& buf, Int32& length)

at System.Web.SessionState.SqlSessionStateStore.SetAndReleaseItemExclusive(HttpContext context, String id, SessionStateStoreData item, Object lockId, Boolean newItem)

at System.Web.SessionState.SessionStateModule.OnReleaseState(Object source, EventArgs eventArgs)

at System.Web.SessionState.SessionStateModule.OnEndRequest(Object source, EventArgs eventArgs)

at System.Web.HttpApplication.SyncEventExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute()

at System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously)

The thread http://forums.microsoft.com/MSDN/ShowPost.aspx?PostID=722552&SiteID=1 gave me an idea what is wrong

"I'm trying to deserialize an object (serialized in .NET 1.1) in .NET 2.0 and one of the child objects is causing a TypeLoadExceptionHolder to be substituted for it in the SerializationInfo during the deserialization process"

Binary deserialization doesn't throw exceptions, but just replace some members(in my case it was enum, that was moved from one namespace to another) with this undocumented TypeLoadExceptionHolder class.

And there is no good way to check , was deserialization successful or not.

Interesting (not really related) hint: Serializing/Deserializing a property which is an enum type.

Posted on Thursday, May 1, 2008 11:13 PM .Net Framework , Testing/Debugging/Logging | Back to top