时间戳列和InvalidOperationException

Question

我最近在linq-to-sql DBML文件中的表中添加了一个时间戳列。加载整个Web服务时都会导致InvalidOperationException（甚至没有运行任何查询）。

例外是：

[InvalidOperationException: System.Data.Linq.Binary cannot be serialized because it does not have a parameterless constructor.]

[InvalidOperationException: Cannot serialize member 'server.DBHandlers.TableName.RowStamp' of type 'System.Data.Linq.Binary', see inner exception for more details.] 
   System.Xml.Serialization.StructModel.CheckSupportedMember(TypeDesc typeDesc, MemberInfo member, Type type) +1549853
   System.Xml.Serialization.StructModel.GetPropertyModel(PropertyInfo propertyInfo) +189
   System.Xml.Serialization.StructModel.GetFieldModel(MemberInfo memberInfo) +146
   System.Xml.Serialization.XmlReflectionImporter.InitializeStructMembers(StructMapping mapping, StructModel model, Boolean openModel, String typeName, RecursionLimiter limiter) +1237
   System.Xml.Serialization.XmlReflectionImporter.ImportStructLikeMapping(StructModel model, String ns, Boolean openModel, XmlAttributes a, RecursionLimiter limiter) +631
   System.Xml.Serialization.XmlReflectionImporter.ImportTypeMapping(TypeModel model, String ns, ImportContext context, String dataType, XmlAttributes a, Boolean repeats, Boolean openModel, RecursionLimiter limiter) +1719

原因是什么？如何解决？

---

根据leppie的请求发布整个堆栈跟踪：

[InvalidOperationException: System.Data.Linq.Binary cannot be serialized because it does not have a parameterless constructor.]

[InvalidOperationException: Cannot serialize member 'server.DBHandlers.TableName.RowStamp' of type 'System.Data.Linq.Binary', see inner exception for more details.]
   System.Xml.Serialization.StructModel.CheckSupportedMember(TypeDesc typeDesc, MemberInfo member, Type type) +1549853
   System.Xml.Serialization.StructModel.GetPropertyModel(PropertyInfo propertyInfo) +189
   System.Xml.Serialization.StructModel.GetFieldModel(MemberInfo memberInfo) +146
   System.Xml.Serialization.XmlReflectionImporter.InitializeStructMembers(StructMapping mapping, StructModel model, Boolean openModel, String typeName, RecursionLimiter limiter) +1237
   System.Xml.Serialization.XmlReflectionImporter.ImportStructLikeMapping(StructModel model, String ns, Boolean openModel, XmlAttributes a, RecursionLimiter limiter) +631
   System.Xml.Serialization.XmlReflectionImporter.ImportTypeMapping(TypeModel model, String ns, ImportContext context, String dataType, XmlAttributes a, Boolean repeats, Boolean openModel, RecursionLimiter limiter) +1719

[InvalidOperationException: There was an error reflecting type 'server.DBHandlers.TableName'.]
   System.Xml.Serialization.XmlReflectionImporter.ImportTypeMapping(TypeModel model, String ns, ImportContext context, String dataType, XmlAttributes a, Boolean repeats, Boolean openModel, RecursionLimiter limiter) +1516787
   System.Xml.Serialization.XmlReflectionImporter.CreateArrayElementsFromAttributes(ArrayMapping arrayMapping, XmlArrayItemAttributes attributes, Type arrayElementType, String arrayElementNs, RecursionLimiter limiter) +412
   System.Xml.Serialization.XmlReflectionImporter.ImportArrayLikeMapping(ArrayModel model, String ns, RecursionLimiter limiter) +337
   System.Xml.Serialization.XmlReflectionImporter.ImportAccessorMapping(MemberMapping accessor, FieldModel model, XmlAttributes a, String ns, Type choiceIdentifierType, Boolean rpc, Boolean openModel, RecursionLimiter limiter) +6535
   System.Xml.Serialization.XmlReflectionImporter.ImportFieldMapping(StructModel parent, FieldModel model, XmlAttributes a, String ns, RecursionLimiter limiter) +210
   System.Xml.Serialization.XmlReflectionImporter.InitializeStructMembers(StructMapping mapping, StructModel model, Boolean openModel, String typeName, RecursionLimiter limiter) +1295

[InvalidOperationException: There was an error reflecting property 'TableName'.]
   System.Xml.Serialization.XmlReflectionImporter.InitializeStructMembers(StructMapping mapping, StructModel model, Boolean openModel, String typeName, RecursionLimiter limiter) +3631
   System.Xml.Serialization.XmlReflectionImporter.ImportStructLikeMapping(StructModel model, String ns, Boolean openModel, XmlAttributes a, RecursionLimiter limiter) +631
   System.Xml.Serialization.XmlReflectionImporter.ImportTypeMapping(TypeModel model, String ns, ImportContext context, String dataType, XmlAttributes a, Boolean repeats, Boolean openModel, RecursionLimiter limiter) +1719

[InvalidOperationException: There was an error reflecting type 'server.DBHandlers.RelatedTableName'.]
   System.Xml.Serialization.XmlReflectionImporter.ImportTypeMapping(TypeModel model, String ns, ImportContext context, String dataType, XmlAttributes a, Boolean repeats, Boolean openModel, RecursionLimiter limiter) +1516787
   System.Xml.Serialization.XmlReflectionImporter.ImportAccessorMapping(MemberMapping accessor, FieldModel model, XmlAttributes a, String ns, Type choiceIdentifierType, Boolean rpc, Boolean openModel, RecursionLimiter limiter) +9555
   System.Xml.Serialization.XmlReflectionImporter.ImportMemberMapping(XmlReflectionMember xmlReflectionMember, String ns, XmlReflectionMember[] xmlReflectionMembers, Boolean rpc, Boolean openModel, RecursionLimiter limiter) +963
   System.Xml.Serialization.XmlReflectionImporter.ImportMembersMapping(XmlReflectionMember[] xmlReflectionMembers, String ns, Boolean hasWrapperElement, Boolean rpc, Boolean openModel, RecursionLimiter limiter) +418

[InvalidOperationException: There was an error reflecting 'getRelatedTable'.]
   System.Xml.Serialization.XmlReflectionImporter.ImportMembersMapping(XmlReflectionMember[] xmlReflectionMembers, String ns, Boolean hasWrapperElement, Boolean rpc, Boolean openModel, RecursionLimiter limiter) +1504534
   System.Xml.Serialization.XmlReflectionImporter.ImportMembersMapping(String elementName, String ns, XmlReflectionMember[] members, Boolean hasWrapperElement, Boolean rpc, Boolean openModel, XmlMappingAccess access) +195
   System.Web.Services.Protocols.SoapReflector.ImportMembersMapping(XmlReflectionImporter xmlImporter, SoapReflectionImporter soapImporter, Boolean serviceDefaultIsEncoded, Boolean rpc, SoapBindingUse use, SoapParameterStyle paramStyle, String elementName, String elementNamespace, Boolean nsIsDefault, XmlReflectionMember[] members, Boolean validate, Boolean openModel, String key, Boolean writeAccess) +388
   System.Web.Services.Protocols.SoapReflector.ReflectMethod(LogicalMethodInfo methodInfo, Boolean client, XmlReflectionImporter xmlImporter, SoapReflectionImporter soapImporter, String defaultNs) +3366

[InvalidOperationException: Method ServiceName.getRelatedTable can not be reflected.]
   System.Web.Services.Protocols.SoapReflector.ReflectMethod(LogicalMethodInfo methodInfo, Boolean client, XmlReflectionImporter xmlImporter, SoapReflectionImporter soapImporter, String defaultNs) +841901
   System.Web.Services.Description.SoapProtocolReflector.ReflectMethod() +142
   System.Web.Services.Description.ProtocolReflector.ReflectBinding(ReflectedBinding reflectedBinding) +1610
   System.Web.Services.Description.ProtocolReflector.Reflect() +710
   System.Web.Services.Description.ServiceDescriptionReflector.ReflectInternal(ProtocolReflector[] reflectors) +565
   System.Web.Services.Description.ServiceDescriptionReflector.Reflect(Type type, String url) +153
   System.Web.Services.Protocols.DocumentationServerType..ctor(Type type, String uri) +203
   System.Web.Services.Protocols.DocumentationServerProtocol.Initialize() +388
   System.Web.Services.Protocols.ServerProtocol.SetContext(Type type, HttpContext context, HttpRequest request, HttpResponse response) +75
   System.Web.Services.Protocols.ServerProtocolFactory.Create(Type type, HttpContext context, HttpRequest request, HttpResponse response, Boolean& abortProcessing) +143

[InvalidOperationException: Unable to handle request.]
   System.Web.Services.Protocols.ServerProtocolFactory.Create(Type type, HttpContext context, HttpRequest request, HttpResponse response, Boolean& abortProcessing) +458731
   System.Web.Services.Protocols.WebServiceHandlerFactory.CoreGetHandler(Type type, HttpContext context, HttpRequest request, HttpResponse response) +285

[InvalidOperationException: Failed to handle request.]
   System.Web.Services.Protocols.WebServiceHandlerFactory.CoreGetHandler(Type type, HttpContext context, HttpRequest request, HttpResponse response) +401482
   System.Web.Services.Protocols.WebServiceHandlerFactory.GetHandler(HttpContext context, String verb, String url, String filePath) +281
   System.Web.Script.Services.ScriptHandlerFactory.GetHandler(HttpContext context, String requestType, String url, String pathTranslated) +89
   System.Web.MaterializeHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute() +425
   System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously) +263

Answer 1

或者将时间戳的类型更改为Byte []。更多[info]：http://geekswithblogs.net/frankw/archive/2008/08/29/serialization-issue-with-timestamp-in-linq-to-sql.aspx

Answer 2

可以通过将DBML中timestamp列的ReadOnly属性更改为true来修复它。