(ASP.NET State Service)Unable to serialize the session state.

在这个异常所描述的类加上[Serializable]关键字

[SerializationException: Type 'YOUR CLASS TYPE' in Assembly 'EasyMan.Utilities.Web.Common, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null' is not marked as serializable.]
   System.Runtime.Serialization.FormatterServices.InternalGetSerializableMembers(RuntimeType type) +4846239
   System.Runtime.Serialization.FormatterServices.GetSerializableMembers(Type type, StreamingContext context) +313
   System.Runtime.Serialization.Formatters.Binary.WriteObjectInfo.InitMemberInfo() +214
   System.Runtime.Serialization.Formatters.Binary.WriteObjectInfo.InitSerialize(Object obj, ISurrogateSelector surrogateSelector, StreamingContext context, SerObjectInfoInit serObjectInfoInit, IFormatterConverter converter, ObjectWriter objectWriter) +719
   System.Runtime.Serialization.Formatters.Binary.ObjectWriter.Write(WriteObjectInfo objectInfo, NameInfo memberNameInfo, NameInfo typeNameInfo) +883
   System.Runtime.Serialization.Formatters.Binary.ObjectWriter.Serialize(Object graph, Header[] inHeaders, __BinaryWriter serWriter, Boolean fCheck) +1431
   System.Runtime.Serialization.Formatters.Binary.BinaryFormatter.Serialize(Stream serializationStream, Object graph, Header[] headers, Boolean fCheck) +249
   System.Web.Util.AltSerialization.WriteValueToStream(Object value, BinaryWriter writer) +1955