Question

我有一个包含DropDownList的表单。我使用SQLServer状态模式来保存SQL Server中的会话。表格显示正确;但是，它在表单提交期间抛出异常。我一直在寻找和尝试一些在线发布但没有运气的建议答案。我在这里做错了什么？

//This is the section where I am building the SelectList Item in the controller

var ListDepartment = ManageUsersMembership.GetDepartment(SessionWrapper.studentBookTrade.SelectedSchoolID);
                // book.DepartmentList = ListDepartment; //new SelectList(ListDepartment, "DepartmentID", "DepartmentName", SessionWrapper.studentBookTrade.SelectedDepartmentID);
                List<SelectListItem> lDepartment = new List<SelectListItem>();
                foreach (var item in ListDepartment)
                {
                    if (SessionWrapper.studentBookTrade.SelectedDepartmentID > 0 && item.DepartmentID == SessionWrapper.studentBookTrade.SelectedDepartmentID)
                    {
                        lDepartment.Add(new SelectListItem { Text = item.DepartmentName, Value = item.DepartmentID.ToString(), Selected = true });
                    }
                    else
                    {
                        lDepartment.Add(new SelectListItem { Text = item.DepartmentName, Value = item.DepartmentID.ToString() });
                    }
                }
                book.DepartmentList = lDepartment;



//this is my property in the Model:

 public virtual IEnumerable<SelectListItem> DepartmentList { get; set; }

//This is the HTML Code in my View:

 @Html.DropDownListFor(model => model.DepartmentID, new SelectList(Model.DepartmentList, "Value", "Text"), "Select Department", new {@class="form-control", id="DepartmentID", onchange = "ValueSelected()" })
                 @Html.ValidationMessageFor(model => model.DepartmentID)



 //The exception

 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.
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 'System.Web.Mvc.SelectList' in Assembly 'System.Web.Mvc, Version=4.0.0.1, Culture=neutral, PublicKeyToken=31bf3856ad364e35' is not marked as serializable.]
   System.Runtime.Serialization.FormatterServices.InternalGetSerializableMembers(RuntimeType type) +10751795
   System.Runtime.Serialization.FormatterServices.GetSerializableMembers(Type type, StreamingContext context) +230
   System.Runtime.Serialization.Formatters.Binary.WriteObjectInfo.InitMemberInfo() +121
   System.Runtime.Serialization.Formatters.Binary.WriteObjectInfo.InitSerialize(Type objectType, ISurrogateSelector surrogateSelector, StreamingContext context, SerObjectInfoInit serObjectInfoInit, IFormatterConverter converter, SerializationBinder binder) +185
   System.Runtime.Serialization.Formatters.Binary.ObjectWriter.Write(WriteObjectInfo objectInfo, NameInfo memberNameInfo, NameInfo typeNameInfo) +565
   System.Runtime.Serialization.Formatters.Binary.ObjectWriter.Serialize(Object graph, Header[] inHeaders, __BinaryWriter serWriter, Boolean fCheck) +446
   System.Runtime.Serialization.Formatters.Binary.BinaryFormatter.Serialize(Stream serializationStream, Object graph, Header[] headers, Boolean fCheck) +131
   System.Web.Util.AltSerialization.WriteValueToStream(Object value, BinaryWriter writer) +1666

[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) +1754
   System.Web.SessionState.SessionStateItemCollection.WriteValueToStreamWithAssert(Object value, BinaryWriter writer) +34
   System.Web.SessionState.SessionStateItemCollection.Serialize(BinaryWriter writer) +628
   System.Web.SessionState.SessionStateUtility.Serialize(SessionStateStoreData item, Stream stream) +240
   System.Web.SessionState.SessionStateUtility.SerializeStoreData(SessionStateStoreData item, Int32 initialStreamSize, Byte[]& buf, Int32& length, Boolean compressionEnabled) +62
   System.Web.SessionState.SqlSessionStateStore.SetAndReleaseItemExclusive(HttpContext context, String id, SessionStateStoreData item, Object lockId, Boolean newItem) +135
   System.Web.SessionState.SessionStateModule.OnReleaseState(Object source, EventArgs eventArgs) +565
   System.Web.SyncEventExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute() +136
   System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously) +69

Answer 1

我觉得你这里太多了。尝试以这种方式更改代码

public IEnumerable<SelectListItem> DepartmentList { get; set; }

我通常使用List但是ienumerable也应该使用

然后在您的视图中，您不需要转换列表

@Html.DropDownListFor(model => model.DepartmentID, Model.DepartmentList, "Select Department", new {@class="form-control", id="DepartmentID", onchange = "ValueSelected()" })

“for”帮助器将为您映射列表。看看这是否有帮助

@HhtmlDropdown抛出SerializationException异常

1 个答案: