c# - 项目创建后立即向 XAML 设计器抛出 NullReference

Question

我尝试在 UWP 项目中打开 XAML 文件后立即抛出此异常

System.NullReferenceException
Object reference not set to an instance of an object.
   at Microsoft.VisualStudio.DesignTools.Platform.Metadata.MetadataStore.GetTypeConverter(Type type)
   at Microsoft.VisualStudio.DesignTools.WindowsXamlDesigner.WindowsUIXamlDesignTimeProperties.ResolveImplementation(IPlatformMetadata platformMetadata, DesignTimePropertyId neutralProperty, IType declaringType, PropertyChangedCallback callback)
   at Microsoft.VisualStudio.DesignTools.WindowsXamlDesigner.WindowsUIXamlDesignTimeProperties.RegisterProperty(IPropertyId neutralPropertyKey, IType declaringType, PropertyChangedCallback callback)
   at Microsoft.VisualStudio.DesignTools.WindowsXamlDesigner.WindowsUIXamlCommonDesignTimeProperties.Initialize(WindowsUIXamlDesignTimeProperties designTimeProperties)
   at Microsoft.VisualStudio.DesignTools.WindowsXamlDesigner.WindowsUIXamlDesignTimeProperties..ctor(IPlatformTypes platformMetadata)
   at Microsoft.VisualStudio.DesignTools.UniversalXamlDesigner.UniversalXamlPlatformMetadata.CreateDesignTimeProperties()
   at Microsoft.VisualStudio.DesignTools.WindowsXamlDesigner.Metadata.WindowsUIXamlPlatformMetadata.Initialize()
   at Microsoft.VisualStudio.DesignTools.WindowsXamlDesigner.WindowsStoreXamlPlatform.Initialize()
   at Microsoft.VisualStudio.DesignTools.Platform.PlatformCreatorBase.CreatePlatform(IPlatformReferenceAssemblyResolver referenceAssemblyResolver)
   at Microsoft.VisualStudio.DesignTools.Designer.Project.ProjectContextManager.GetProjectContext(IHostProject project, IPlatform platform, Boolean create)
   at Microsoft.VisualStudio.DesignTools.Designer.Project.ProjectContextManager.GetSourceItemContext(IHostSourceItem sourceItem)
   at Microsoft.VisualStudio.DesignTools.Designer.DesignerService.CreateDesigner(IHostSourceItem item, IHostTextEditor editor, CancellationToken cancelToken)
   at Microsoft.VisualStudio.DesignTools.DesignerContract.Isolation.Remoting.RemoteDesignerService.<>c__DisplayClass12_0.<Microsoft.VisualStudio.DesignTools.DesignerContract.Isolation.Remoting.IRemoteDesignerService.CreateDesigner>b__0(CancellationToken cancelToken)
   at Microsoft.VisualStudio.DesignTools.DesignerContract.Isolation.Remoting.RemoteDesignerService.<>c__DisplayClass6_0`1.<MarshalInWithCancellation>b__0()
   at Microsoft.VisualStudio.DesignTools.DesignerContract.Isolation.Remoting.STAMarshaler.Call.InvokeWorker()

System.NullReferenceException
Object reference not set to an instance of an object.

Server stack trace: 
   at Microsoft.VisualStudio.DesignTools.DesignerContract.Isolation.Remoting.STAMarshaler.WaitForCompletion(NestedCallContext nestedCallContext, BlockingCall call, WaitHandle timeoutSignal)
   at Microsoft.VisualStudio.DesignTools.DesignerContract.Isolation.Remoting.STAMarshaler.MarshalInSynchronous(Action action, Int32 targetApartmentId, CancellationToken cancelToken, CallModality callModality, String methodName, String filePath, Int32 lineNumber)
   at Microsoft.VisualStudio.DesignTools.DesignerContract.Isolation.Remoting.STAMarshaler.MarshalIn(Action action, Int32 targetApartmentId, CancellationToken cancelToken, CallSynchronizationMode syncMode, CallModality callModality, String methodName, String filePath, Int32 lineNumber)
   at Microsoft.VisualStudio.DesignTools.DesignerContract.Isolation.Remoting.ThreadMarshaler.MarshalIn(IRemoteObject targetObject, Action action, CancellationToken cancelToken, CallSynchronizationMode syncMode, CallModality callModality, ApartmentState apartmentState, String memberName, String filePath, Int32 lineNumber)
   at Microsoft.VisualStudio.DesignTools.DesignerContract.Isolation.Remoting.RemoteDesignerService.MarshalInWithCancellation[TResult](IRemoteCancellationToken remoteToken, Func`2 func, ApartmentState apartmentState)
   at Microsoft.VisualStudio.DesignTools.DesignerContract.Isolation.Remoting.RemoteDesignerService.Microsoft.VisualStudio.DesignTools.DesignerContract.Isolation.Remoting.IRemoteDesignerService.CreateDesigner(IRemoteHostProject remoteProject, IRemoteHostSourceItem remoteItem, IRemoteHostTextEditor remoteEditor, IRemoteCancellationToken remoteToken)
   at System.Runtime.Remoting.Messaging.StackBuilderSink._PrivateProcessMessage(IntPtr md, Object[] args, Object server, Object[]& outArgs)
   at System.Runtime.Remoting.Messaging.StackBuilderSink.SyncProcessMessage(IMessage msg)

Exception rethrown at [0]: 
   at System.Runtime.Remoting.Proxies.RealProxy.HandleReturnMessage(IMessage reqMsg, IMessage retMsg)
   at System.Runtime.Remoting.Proxies.RealProxy.PrivateInvoke(MessageData& msgData, Int32 type)
   at Microsoft.VisualStudio.DesignTools.DesignerContract.Isolation.Remoting.IRemoteDesignerService.CreateDesigner(IRemoteHostProject remoteProject, IRemoteHostSourceItem remoteItem, IRemoteHostTextEditor remoteEditor, IRemoteCancellationToken cancelToken)
   at Microsoft.VisualStudio.DesignTools.DesignerContract.Isolation.Remoting.LocalDesignerService.CreateDesignerImpl(IRemoteDesignerService ds, IHostSourceItem item, IHostTextEditor editor, RemoteCancellationToken remoteCancelToken)
   at Microsoft.VisualStudio.DesignTools.DesignerContract.Isolation.Remoting.LocalDesignerService.<>c__DisplayClass14_0.<Microsoft.VisualStudio.DesignTools.DesignerContract.IDesignerService.CreateDesigner>b__0(IRemoteDesignerService ds, RemoteCancellationToken remoteToken)
   at Microsoft.VisualStudio.DesignTools.DesignerContract.Isolation.Remoting.LocalDesignerService.<>c__DisplayClass5_0`1.<MarshalOutWithCancellation>b__0(IRemoteDesignerService ds)
   at Microsoft.VisualStudio.DesignTools.DesignerContract.Isolation.Remoting.ThreadMarshaler.<>c__DisplayClass27_0`1.<MarshalOut>b__0()
   at Microsoft.VisualStudio.DesignTools.DesignerContract.Isolation.Remoting.STAMarshaler.Call.InvokeWorker()

System.NullReferenceException
Object reference not set to an instance of an object.
   at Microsoft.VisualStudio.DesignTools.DesignerContract.Isolation.Remoting.STAMarshaler.WaitForCompletion(NestedCallContext nestedCallContext, BlockingCall call, WaitHandle timeoutSignal)
   at Microsoft.VisualStudio.DesignTools.DesignerContract.Isolation.Remoting.STAMarshaler.MarshalOutSynchronous(Action action, Int32 targetApartmentId, WaitHandle aborted, WaitHandle timeoutSignal, CancellationToken cancelToken, String methodName, String filePath, Int32 lineNumber)
   at Microsoft.VisualStudio.DesignTools.DesignerContract.Isolation.Remoting.STAMarshaler.MarshalOut(Action action, Int32 targetApartmentId, WaitHandle aborted, CancellationToken cancelToken, CallSynchronizationMode syncMode, WaitHandle timeoutSignal, String methodName, String filePath, Int32 lineNumber)
   at Microsoft.VisualStudio.DesignTools.DesignerContract.Isolation.Remoting.ThreadMarshaler.MarshalOut[TValue](RemoteHandle`1 targetObject, Action action, CancellationToken cancelToken, CallSynchronizationMode syncMode, ApartmentState apartmentState, String methodName, String filePath, Int32 lineNumber)
   at Microsoft.VisualStudio.DesignTools.DesignerContract.Isolation.Remoting.ThreadMarshaler.MarshalOut[TValue](RemoteHandle`1 targetObject, Action`1 action, CancellationToken cancelToken, CallSynchronizationMode syncMode, ApartmentState apartmentState, String methodName, String filePath, Int32 lineNumber)
   at Microsoft.VisualStudio.DesignTools.DesignerContract.Isolation.Remoting.LocalDesignerService.MarshalOutWithCancellation[TResult](CancellationToken cancelToken, Func`3 func, ApartmentState apartmentState)
   at Microsoft.VisualStudio.DesignTools.DesignerContract.Isolation.Remoting.LocalDesignerService.Microsoft.VisualStudio.DesignTools.DesignerContract.IDesignerService.CreateDesigner(IHostSourceItem item, IHostTextEditor editor, CancellationToken cancelToken)
   at Microsoft.VisualStudio.DesignTools.DesignerContract.IsolatedDesignerService.IsolatedDesignerView.CreateDesignerViewInfo(CancellationToken cancelToken)

我什么都没做，这个 Visual Studio 在我从 8.1 升级到 10 后就安装好了。在这个Visual Studio 2015之前，我曾经有过VS2013，升级换VS2015后直接卸载了

我找到了一篇关于它的帖子:https://social.msdn.microsoft.com/Forums/en-US/59ee2840-4329-413a-80ce-5c6a2f1390cc/rtm-known-issue-opening-a-xaml-page-from-a-c-uwp-in-visual-studio-2015-may-cause-the-xaml?forum=Win10SDKToolsIssues

但这并没有帮助

我的 XAML 有问题吗？

Answer 1

这对我适用于 2 种不同的 HP 产品(HP 设置“平台”环境变量)。

在系统->高级系统设置->环境变量中删除“平台”环境变量...

在我的例子中它说 =HPD