我正在处理我的WP7应用程序的当前状态，在OnNavigatedFrom和To事件中，以便如果应用程序被挂起或导航到另一个页面，则将状态保存到内置的PhoneApplicationService状态。
我有一个简单的ViewModel，我将其转储到状态中，以使生活更轻松。在我的应用程序内导航到不同页面时，状态被很好地存储和恢复（即我认为它在此时进行序列化）。但是，当我挂起应用程序（即开始按钮）时，我会收到一个未处理的序列化错误，并且堆栈跟踪没有给我任何关于失败原因的线索。
我已经尝试将实际调用包装在try catch块中，以尝试查看出错原因，但这并没有帮助-运行时在使用对象时与仅在页面之间存储时有所不同。
这是我的代码：
protected override void OnNavigatedFrom(NavigationEventArgs args)
{
appService.State["TournamentViewModel"] = tournamentViewModel;
base.OnNavigatedFrom(args);
}
protected override void OnNavigatedTo(NavigationEventArgs args)
{
if (appService.State.ContainsKey("TournamentViewModel"))
{
tournamentViewModel = (TournamentViewModel)appService.State["TournamentViewModel"];
}
base.OnNavigatedTo(args);
}
这是生成的错误 - 我真的无法弄清问题出在哪里 - 我该如何更好地调试？
异常信息： 消息：“SecurityException” 内部异常：“无法评估表达式”
堆栈跟踪：
at System.Runtime.Serialization.DataContract.DataContractCriticalHelper.CreateGetOnlyCollectionDataContract(Int32 id, RuntimeTypeHandle typeHandle, Type type)
at System.Runtime.Serialization.DataContract.DataContractCriticalHelper.GetGetOnlyCollectionDataContractSkipValidation(Int32 id, RuntimeTypeHandle typeHandle, Type type)
at System.Runtime.Serialization.DataContract.GetGetOnlyCollectionDataContractSkipValidation(Int32 id, RuntimeTypeHandle typeHandle, Type type)
at System.Runtime.Serialization.XmlObjectSerializerContext.GetDataContractSkipValidation(Int32 typeId, RuntimeTypeHandle typeHandle, Type type)
at System.Runtime.Serialization.XmlObjectSerializerWriteContext.SerializeWithXsiType(XmlWriterDelegator xmlWriter, Object obj, RuntimeTypeHandle objectTypeHandle, Type objectType, Int32 declaredTypeID, RuntimeTypeHandle declaredTypeHandle, Type declaredType)
at System.Runtime.Serialization.XmlObjectSerializerWriteContext.InternalSerialize(XmlWriterDelegator xmlWriter, Object obj, Boolean isDeclaredType, Boolean writeXsiType, Int32 declaredTypeID, RuntimeTypeHandle declaredTypeHandle)
at System.Runtime.Serialization.XmlObjectSerializerWriteContext.InternalSerializeReference(XmlWriterDelegator xmlWriter, Object obj, Boolean isDeclaredType, Boolean writeXsiType, Int32 declaredTypeID, RuntimeTypeHandle declaredTypeHandle)
at System.Reflection.RuntimeMethodInfo.InternalInvoke(RuntimeMethodInfo rtmi, Object obj, BindingFlags invokeAttr, Binder binder, Object parameters, CultureInfo culture, Boolean isBinderDefault, Assembly caller, Boolean verifyAccess, StackCrawlMark& stackMark)
at System.Reflection.RuntimeMethodInfo.InternalInvoke(Object obj, BindingFlags invokeAttr, Binder binder, Object[] parameters, CultureInfo culture, StackCrawlMark& stackMark)
at System.Reflection.MethodBase.Invoke(Object obj, Object[] parameters)
at System.Runtime.Serialization.XmlFormatWriter.InternalSerialize(MethodInfo methodInfo, Object memberValue, Type memberType, Boolean writeXsiType, XmlObjectSerializerWriteContext context, XmlWriterDelegator xmlWriter)
at System.Runtime.Serialization.XmlFormatWriter.WriteValue(Type memberType, Object memberValue, Boolean writeXsiType, XmlObjectSerializerWriteContext context, XmlWriterDelegator xmlWriter)
at System.Runtime.Serialization.XmlFormatWriter.WriteMember(SerializingObject serObj, Int32 memberIndex, ClassDataContract derivedMostClassContract)
at System.Runtime.Serialization.XmlFormatWriter.WriteClass(CallStackElement`1 callStackElement)
at System.Runtime.Serialization.XmlFormatWriter.Serialize(XmlObjectSerializerWriteContext context)
at System.Runtime.Serialization.XmlFormatWriter.InitializeCallStack(XmlWriterDelegator xmlWriterDel, Object obj, XmlObjectSerializerWriteContext writeContext, DataContract contract)
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)
at System.Runtime.Serialization.DataContractSerializer.InternalWriteObject(XmlWriterDelegator writer, Object graph)
at System.Runtime.Serialization.XmlObjectSerializer.WriteObjectHandleExceptions(XmlWriterDelegator writer, Object graph)
at System.Runtime.Serialization.XmlObjectSerializer.WriteObject(XmlDictionaryWriter writer, Object graph)
at System.Runtime.Serialization.XmlObjectSerializer.WriteObject(Stream stream, Object graph)
at Microsoft.Phone.Shell.StreamPersister.Serialize(IDictionary`2 dictionary, IEnumerable`1 knownTypes)
at Microsoft.Phone.Shell.StreamPersister.Save(ShellPageManager shellPageManager, String key, IDictionary`2 dictionary, IEnumerable`1 knownTypes)
at Microsoft.Phone.Shell.PhoneApplicationService.FireDeactivated()
at Microsoft.Phone.Execution.NativeEmInterop.FireOnPause()
更新：通过试错，我发现问题出在AppBar上，它似乎不可序列化。我用[IgnoreDataMember]标记了它，现在它会在其他问题上抛出更有意义的错误。我仍然想知道是否有任何简单的方法来捕获这些信息...