我遇到了这种情况：
Custom Control -> Navigate to its Settings Page -> Tap on a button in the Settings Page -> Show a PhotoChooserTask
所以，假设这个自定义控件只显示从用户库加载的图像。
点击用户控件时，我会显示一个XAML设置页面，其中有一个按钮可以从图库中加载图像，此按钮会启动PhotoChooserTask。
现在，问题是它在启动任务后立即抛出异常。
这是堆栈跟踪：
+ $exception {System.Runtime.Serialization.InvalidDataContractException: Type 'System.Windows.UIElement' cannot be serialized. Consider marking it with the DataContractAttribute attribute, and marking all of its members you want serialized with the DataMemberAttribute attribute. Alternatively, you can ensure that the type is public and has a parameterless constructor - all public members of the type will then be serialized, and no attributes will be required.
at System.Runtime.Serialization.DataContract.DataContractCriticalHelper.ThrowInvalidDataContractException(String message, Type type)
at System.Runtime.Serialization.DataContract.DataContractCriticalHelper.CreateDataContract(Int32 id, RuntimeTypeHandle typeHandle, Type type)
at System.Runtime.Serialization.DataContract.DataContractCriticalHelper.GetDataContractSkipValidation(Int32 id, RuntimeTypeHandle typeHandle, Type type)
at System.Runtime.Serialization.DataContract.GetDataContractSkipValidation(Int32 id, RuntimeTypeHandle typeHandle, Type type)
at System.Runtime.Serialization.DataContract.GetDataContract(RuntimeTypeHandle typeHandle, Type type, SerializationMode mode)
at System.Runtime.Serialization.ClassDataContract.ClassDataContractCriticalHelper..ctor(Type type)
at System.Runtime.Serialization.ClassDataContract..ctor(Type type)
at System.Runtime.Serialization.DataContract.DataContractCriticalHelper.CreateDataContract(Int32 id, RuntimeTypeHandle typeHandle, Type type)
at System.Runtime.Serialization.DataContract.DataContractCriticalHelper.GetDataContractSkipValidation(Int32 id, RuntimeTypeHandle typeHandle, Type type)
at System.Runtime.Serialization.DataContract.GetDataContractSkipValidation(Int32 id, RuntimeTypeHandle typeHandle, Type type)
at System.Runtime.Serialization.DataContract.GetDataContract(RuntimeTypeHandle typeHandle, Type type, SerializationMode mode)
at System.Runtime.Serialization.ClassDataContract.ClassDataContractCriticalHelper..ctor(Type type)
at System.Runtime.Serialization.ClassDataContract..ctor(Type type)
at System.Runtime.Serialization.DataContract.DataContractCriticalHelper.CreateDataContract(Int32 id, RuntimeTypeHandle typeHandle, Type type)
at System.Runtime.Serialization.DataContract.DataContractCriticalHelper.GetDataContractSkipValidation(Int32 id, RuntimeTypeHandle typeHandle, Type type)
at System.Runtime.Serialization.DataContract.GetDataContractSkipValidation(Int32 id, RuntimeTypeHandle typeHandle, Type type)
at System.Runtime.Serialization.DataContract.GetDataContract(RuntimeTypeHandle typeHandle, Type type, SerializationMode mode)
at System.Runtime.Serialization.ClassDataContract.ClassDataContractCriticalHelper..ctor(Type type)
at System.Runtime.Serialization.ClassDataContract..ctor(Type type)
at System.Runtime.Serialization.DataContract.DataContractCriticalHelper.CreateDataContract(Int32 id, RuntimeTypeHandle typeHandle, Type type)
at System.Runtime.Serialization.DataContract.DataContractCriticalHelper.GetDataContractSkipValidation(Int32 id, RuntimeTypeHandle typeHandle, Type type)
at System.Runtime.Serialization.DataContract.GetDataContractSkipValidation(Int32 id, RuntimeTypeHandle typeHandle, Type type)
at System.Runtime.Serialization.DataContract.GetDataContract(RuntimeTypeHandle typeHandle, Type type, SerializationMode mode)
at System.Runtime.Serialization.ClassDataContract.ClassDataContractCriticalHelper..ctor(Type type)
at System.Runtime.Serialization.ClassDataContract..ctor(Type type)
at System.Runtime.Serialization.DataContract.DataContractCriticalHelper.CreateDataContract(Int32 id, RuntimeTypeHandle typeHandle, Type type)
at System.Runtime.Serialization.DataContract.DataContractCriticalHelper.GetDataContractSkipValidation(Int32 id, RuntimeTypeHandle typeHandle, Type type)
at System.Runtime.Serialization.DataContract.GetDataContractSkipValidation(Int32 id, RuntimeTypeHandle typeHandle, Type type)
at System.Runtime.Serialization.DataContract.GetDataContract(RuntimeTypeHandle typeHandle, Type type, SerializationMode mode)
at System.Runtime.Serialization.ClassDataContract.ClassDataContractCriticalHelper..ctor(Type type)
at System.Runtime.Serialization.ClassDataContract..ctor(Type type)
at System.Runtime.Serialization.DataContract.DataContractCriticalHelper.CreateDataContract(Int32 id, RuntimeTypeHandle typeHandle, Type type)
at System.Runtime.Serialization.DataContract.DataContractCriticalHelper.GetDataContractSkipValidation(Int32 id, RuntimeTypeHandle typeHandle, Type type)
at System.Runtime.Serialization.DataContract.GetDataContractSkipValidation(Int32 id, RuntimeTypeHandle typeHandle, Type type)
at System.Runtime.Serialization.DataContract.GetDataContract(RuntimeTypeHandle typeHandle, Type type, SerializationMode mode)
at System.Runtime.Serialization.ClassDataContract.ClassDataContractCriticalHelper..ctor(Type type)
at System.Runtime.Serialization.ClassDataContract..ctor(Type type)
at System.Runtime.Serialization.DataContract.DataContractCriticalHelper.CreateDataContract(Int32 id, RuntimeTypeHandle typeHandle, Type type)
at System.Runtime.Serialization.DataContract.DataContractCriticalHelper.GetDataContractSkipValidation(Int32 id, RuntimeTypeHandle typeHandle, Type type)
at System.Runtime.Serialization.DataContract.GetDataContractSkipValidation(Int32 id, RuntimeTypeHandle typeHandle, Type type)
at System.Runtime.Serialization.DataContract.GetDataContract(RuntimeTypeHandle typeHandle, Type type, SerializationMode mode)
at System.Runtime.Serialization.ClassDataContract.ClassDataContractCriticalHelper..ctor(Type type)
at System.Runtime.Serialization.ClassDataContract..ctor(Type type)
at System.Runtime.Serialization.DataContract.DataContractCriticalHelper.CreateDataContract(Int32 id, RuntimeTypeHandle typeHandle, Type type)
at System.Runtime.Serialization.DataContract.DataContractCriticalHelper.GetDataContractSkipValidation(Int32 id, RuntimeTypeHandle typeHandle, Type type)
at System.Runtime.Serialization.DataContract.GetDataContractSkipValidation(Int32 id, RuntimeTypeHandle typeHandle, Type type)
at System.Runtime.Serialization.DataContract.GetDataContract(RuntimeTypeHandle typeHandle, Type type, SerializationMode mode)
at System.Runtime.Serialization.XmlObjectSerializerContext.GetDataContract(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 WriteKeyValueOfstringanyTypeToXml(XmlWriterDelegator , Object , XmlObjectSerializerWriteContext , ClassDataContract )
at System.Runtime.Serialization.ClassDataContract.WriteXmlValue(XmlWriterDelegator xmlWriter, Object obj, XmlObjectSerializerWriteContext context)
at WriteArrayOfKeyValueOfstringanyTypeToXml(XmlWriterDelegator , Object , XmlObjectSerializerWriteContext , CollectionDataContract )
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, DataContractResolver dataContractResolver)
at System.Runtime.Serialization.DataContractSerializer.InternalWriteObject(XmlWriterDelegator writer, Object graph, DataContractResolver dataContractResolver)
at System.Runtime.Serialization.XmlObjectSerializer.WriteObjectHandleExceptions(XmlWriterDelegator writer, Object graph, DataContractResolver dataContractResolver)
at System.Runtime.Serialization.XmlObjectSerializer.WriteObject(XmlDictionaryWriter writer, Object graph)
at System.Runtime.Serialization.XmlObjectSerializer.WriteObject(Stream stream, Object graph)
at Microsoft.Phone.Shell.BaseStreamPersister.Serialize(IDictionary`2 dictionary, IEnumerable`1 knownTypes)
at Microsoft.Phone.Shell.PhoneApplicationService.SaveState()
at Microsoft.Phone.Shell.PhoneApplicationService.FireDeactivated(UInt32 reason)
at Microsoft.Phone.TaskModel.Interop.ITask.Pause.Invoke(UInt32 reason)
at Microsoft.Phone.TaskModel.Interop.Task.FireOnPause(UInt32 reason)} System.Exception {System.Runtime.Serialization.InvalidDataContractException}
我理解这与应用程序的状态完全相关，我认为这是因为操作系统在任务完成后试图“冻结”应用程序以恢复其状态。
我不明白这个系统是如何工作的以及我必须做些什么来避免异常并使其正确地序列化我的组件。
请记住，我有多个级别的继承（例如`UserControl - ＆gt; Custom 1 - ＆gt; Custom 2 - ＆gt; Custom 3 - ＆gt; Current Custom Control）。
有什么想法吗？
编辑：
经过一些实验后，我发现每次离开应用程序时都会抛出异常，但前提是我在设置页面中。
如果我通过启动任务或点击Windows按钮离开它并不重要。
现在，这是我使用外部库（Coding4Fun Toolkit）的唯一页面，所以我猜这是问题所在，但我仍然没有得到如何解决它或如果这是库的错误！
答案 0 :(得分：0)
时抛出此
InvalidDataContractException
DataContractSerializer或NetDataContractSerializer在序列化和反序列化期间遇到无效的数据协定。 （来自MSDN）
如果您尝试在UserControl区域内的应用程序中序列化某些内容，那么您还没有正确实现序列化......这可以修复。
但是，如果您的应用程序中没有序列化或反序列化代码，则此序列化由您添加到应用程序的控件或类似代码执行... 此为真，然后你有一个更大的问题，因为你可能无法访问代码来解决问题。
参考您的评论'因为异常的消息建议我这样做'，您是否在之前使用序列化获得此Exception？