WPF設計器無法加載

Question

在Win7上使用Visual Studio 2012。

我最近通過將Window>用< UserControl>替換爲< Control.Resources>，將WPF應用程序轉換爲WPF用戶控件。爲了安全起見，我也將代碼隱藏從UserControl繼承，但是在某些時候，這打破了應用程序，我無法再在設計模式下查看它。我得到的是這樣的廢話：

System.NullReferenceException 
Object reference not set to an instance of an object. 
    at Microsoft.Expression.DesignHost.Isolation.Remoting.STAMarshaler.WaitForCompletion(NestedCallContext nestedCallContext, BlockingCall call, WaitHandle timeoutSignal) 
    at Microsoft.Expression.DesignHost.Isolation.Remoting.STAMarshaler.MarshalOutSynchronous(Action action, Int32 targetApartmentId, WaitHandle aborted, WaitHandle timeoutSignal) 
    at Microsoft.Expression.DesignHost.Isolation.Remoting.STAMarshaler.MarshalOut(Action action, Int32 targetApartmentId, WaitHandle aborted, CallSynchronizationMode syncMode, WaitHandle timeoutSignal) 
    at Microsoft.Expression.DesignHost.Isolation.Remoting.ThreadMarshaler.MarshalOut[TValue](RemoteHandle`1 targetObject, Action action, CallSynchronizationMode syncMode) 
    at Microsoft.Expression.DesignHost.Isolation.Remoting.ThreadMarshaler.MarshalOut[TResult,TValue](RemoteHandle`1 targetObject, Func`2 func, CallSynchronizationMode syncMode) 
    at Microsoft.Expression.DesignHost.Isolation.Remoting.LocalDesignerService.CreateDesignerImpl(IHostSourceItem item, IHostTextEditor editor, RemoteCancellationToken remoteCancelToken) 
    at Microsoft.Expression.DesignHost.Isolation.Remoting.LocalDesignerService.<>c__DisplayClass12.<Microsoft.Expression.DesignHost.IDesignerService.CreateDesigner>b__11(RemoteCancellationToken remoteToken) 
    at Microsoft.Expression.DesignHost.Isolation.Remoting.LocalDesignerService.CallWithCancellation[TResult](CancellationToken cancelToken, Func`2 func) 
    at Microsoft.Expression.DesignHost.Isolation.Remoting.LocalDesignerService.Microsoft.Expression.DesignHost.IDesignerService.CreateDesigner(IHostSourceItem item, IHostTextEditor editor, CancellationToken cancelToken) 
    at Microsoft.Expression.DesignHost.IsolatedDesignerService.IsolatedDesignerView.CreateDesignerViewInfo(CancellationToken cancelToken) 

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

Server stack trace: 
    at Microsoft.Expression.DesignHost.Isolation.Remoting.STAMarshaler.WaitForCompletion(NestedCallContext nestedCallContext, BlockingCall call, WaitHandle timeoutSignal) 
    at Microsoft.Expression.DesignHost.Isolation.Remoting.STAMarshaler.MarshalIn(Action action, Int32 targetApartmentId) 
    at Microsoft.Expression.DesignHost.Isolation.Remoting.ThreadMarshaler.MarshalIn(IRemoteObject targetObject, Action action) 
    at Microsoft.Expression.DesignHost.Isolation.Remoting.ThreadMarshaler.MarshalIn[TResult](IRemoteObject targetObject, Func`1 func) 
    at Microsoft.Expression.DesignHost.Isolation.Remoting.RemoteDesignerService.Microsoft.Expression.DesignHost.Isolation.Remoting.IRemoteDesignerService.CreateDesigner(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.Expression.DesignHost.Isolation.Remoting.IRemoteDesignerService.CreateDesigner(IRemoteHostSourceItem remoteItem, IRemoteHostTextEditor remoteEditor, IRemoteCancellationToken cancelToken) 
    at Microsoft.Expression.DesignHost.Isolation.Remoting.LocalDesignerService.<>c__DisplayClass8.<CreateDesignerImpl>b__6(IRemoteDesignerService d) 
    at Microsoft.Expression.DesignHost.Isolation.Remoting.ThreadMarshaler.<>c__DisplayClass4`2.<MarshalOut>b__3() 
    at Microsoft.Expression.DesignHost.Isolation.Remoting.STAMarshaler.Call.InvokeWorker() 

System.NullReferenceException 
Object reference not set to an instance of an object. 
    at Microsoft.Expression.DesignHost.Isolation.Remoting.STAMarshaler.WaitForCompletion(NestedCallContext nestedCallContext, BlockingCall call, WaitHandle timeoutSignal) 
    at Microsoft.Expression.DesignHost.Isolation.Remoting.STAMarshaler.MarshalOutSynchronous(Action action, Int32 targetApartmentId, WaitHandle aborted, WaitHandle timeoutSignal) 
    at Microsoft.Expression.DesignHost.Isolation.Remoting.STAMarshaler.MarshalOut(Action action, Int32 targetApartmentId, WaitHandle aborted, CallSynchronizationMode syncMode, WaitHandle timeoutSignal) 
    at Microsoft.Expression.DesignHost.Isolation.Remoting.ThreadMarshaler.MarshalOut[TValue](RemoteHandle`1 targetObject, Action action, CallSynchronizationMode syncMode) 
    at Microsoft.Expression.DesignHost.Isolation.Remoting.ThreadMarshaler.MarshalOut[TResult,TValue](RemoteHandle`1 targetObject, Func`2 func, CallSynchronizationMode syncMode) 
    at Microsoft.Expression.DesignHost.Isolation.Remoting.LocalHostProjectService.Microsoft.Expression.DesignHost.IHostProjectService.FindProject(FindProjectCriteria criteria, String criteriaValue) 
    at Microsoft.Expression.DesignSurface.Project.ProjectContextManager.FindApplicationProjectContext(XamlProjectContext requestingContext) 
    at Microsoft.Expression.DesignSurface.Project.XamlProjectContext.get_Application() 
    at Microsoft.Expression.DesignSurface.Documents.SceneDocument.GetApplicationDocument(IXamlProjectContext activeContext) 
    at Microsoft.Expression.DesignSurface.Documents.SceneDocument.get_ApplicationSceneDocument() 
    at Microsoft.Expression.DesignSurface.DocumentViewContext.CreateAndOpenView(ISourceItemContext sourceItem, CancellationToken cancelToken, Boolean activate, Boolean ensureOpenInHost, Boolean suppressUI) 
    at Microsoft.Expression.DesignSurface.DesignerService.CreateDesigner(IHostSourceItem item, IHostTextEditor editor, CancellationToken cancelToken) 
    at Microsoft.Expression.DesignHost.Isolation.Remoting.RemoteDesignerService.<>c__DisplayClass10.<>c__DisplayClass12.<Microsoft.Expression.DesignHost.Isolation.Remoting.IRemoteDesignerService.CreateDesigner>b__f(CancellationToken cancelToken) 
    at Microsoft.Expression.DesignHost.Isolation.Remoting.RemoteDesignerService.CallWithCancellation[TResult](IRemoteCancellationToken remoteToken, Func`2 func) 
    at Microsoft.Expression.DesignHost.Isolation.Remoting.RemoteDesignerService.<>c__DisplayClass10.<Microsoft.Expression.DesignHost.Isolation.Remoting.IRemoteDesignerService.CreateDesigner>b__e() 
    at Microsoft.Expression.DesignHost.Isolation.Remoting.ThreadMarshaler.<>c__DisplayClass16`1.<MarshalIn>b__15() 
    at Microsoft.Expression.DesignHost.Isolation.Remoting.STAMarshaler.Call.InvokeWorker() 

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

Server stack trace: 
    at Microsoft.Expression.DesignHost.Isolation.Remoting.STAMarshaler.WaitForCompletion(NestedCallContext nestedCallContext, BlockingCall call, WaitHandle timeoutSignal) 
    at Microsoft.Expression.DesignHost.Isolation.Remoting.STAMarshaler.MarshalIn(Action action, Int32 targetApartmentId) 
    at Microsoft.Expression.DesignHost.Isolation.Remoting.ThreadMarshaler.MarshalIn(IRemoteObject targetObject, Action action) 
    at Microsoft.Expression.DesignHost.Isolation.Remoting.ThreadMarshaler.MarshalIn[TResult](IRemoteObject targetObject, Func`1 func) 
    at Microsoft.Expression.DesignHost.Isolation.Remoting.RemoteHostProjectService.Microsoft.Expression.DesignHost.Isolation.Remoting.IRemoteHostProjectService.FindProject(FindProjectCriteria criteria, String criteriaValue) 
    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.Expression.DesignHost.Isolation.Remoting.IRemoteHostProjectService.FindProject(FindProjectCriteria criteria, String criteriaValue) 
    at Microsoft.Expression.DesignHost.Isolation.Remoting.LocalHostProjectService.<>c__DisplayClass7.<Microsoft.Expression.DesignHost.IHostProjectService.FindProject>b__6(IRemoteHostProjectService ps) 
    at Microsoft.Expression.DesignHost.Isolation.Remoting.ThreadMarshaler.<>c__DisplayClass4`2.<MarshalOut>b__3() 
    at Microsoft.Expression.DesignHost.Isolation.Remoting.STAMarshaler.Call.InvokeWorker() 

System.NullReferenceException 
Object reference not set to an instance of an object. 
    at MS.Internal.VSUtilities.GetBuildAction(IVsHierarchy hierarchy, UInt32 itemid) 
    at Microsoft.VisualStudio.ExpressionHost.HostServices.HostSourceItem.<>c__DisplayClass9.<Microsoft.Expression.DesignHost.IHostSourceItem.get_BuildItemType>b__7() 
    at Microsoft.Expression.DesignHost.Isolation.Remoting.STAMarshaler.Call.InvokeWorker() 
    at Microsoft.Expression.DesignHost.Isolation.Remoting.STAMarshaler.Call.Invoke(Boolean waitingInExternalCall) 
    at Microsoft.Expression.DesignHost.Isolation.Remoting.STAMarshaler.InvokeCall(Call call) 
    at Microsoft.Expression.DesignHost.Isolation.Remoting.STAMarshaler.DirectInvoke(Action action, Int32 sourceApartmentId, Int32 targetApartmentId, Int32 originId, WaitHandle aborted) 
    at Microsoft.Expression.DesignHost.Isolation.Remoting.STAMarshaler.DirectInvokeInbound(Action action, Int32 targetApartmentId) 
    at Microsoft.Expression.DesignHost.Isolation.Remoting.STAMarshaler.MarshalIn(Action action, Int32 targetApartmentId) 
    at Microsoft.Expression.DesignHost.Isolation.Remoting.ThreadMarshaler.MarshalIn(IRemoteObject targetObject, Action action) 
    at Microsoft.VisualStudio.ExpressionHost.HostServices.HostSourceItem.Microsoft.Expression.DesignHost.IHostSourceItem.get_BuildItemType() 
    at Microsoft.Expression.HostUtility.Extensions.HostExtensions.<HasApplicationDocument>b__0(IHostSourceItem i) 
    at System.Linq.Enumerable.Any[TSource](IEnumerable`1 source, Func`2 predicate) 
    at Microsoft.Expression.HostUtility.Extensions.HostExtensions.HasApplicationDocument(IHostProject hostProject) 
    at Microsoft.VisualStudio.ExpressionHost.HostServices.HostProjectService.FindApplicationProject(String projectPath) 
    at Microsoft.VisualStudio.ExpressionHost.HostServices.HostProjectService.<FindProjectsInternal>d__30.MoveNext() 
    at System.Linq.Enumerable.FirstOrDefault[TSource](IEnumerable`1 source) 
    at Microsoft.VisualStudio.ExpressionHost.HostServices.HostProjectService.Microsoft.Expression.DesignHost.IHostProjectService.FindProject(FindProjectCriteria criteria, String criteriaValue) 
    at Microsoft.Expression.DesignHost.Isolation.Remoting.RemoteHostProjectService.<>c__DisplayClass1d.<Microsoft.Expression.DesignHost.Isolation.Remoting.IRemoteHostProjectService.FindProject>b__1c() 
    at Microsoft.Expression.DesignHost.Isolation.Remoting.ThreadMarshaler.<>c__DisplayClass16`1.<MarshalIn>b__15() 
    at Microsoft.Expression.DesignHost.Isolation.Remoting.STAMarshaler.Call.InvokeWorker() 

幾個googlings我所在，這是一個熱點問題，2012年，但似乎都但此後蒸發後。但現在我沒有什麼可以繼續下去的！我所有的程序集都是3.5+（2.0程序集是當時的一個已知問題），我嘗試刪除引用，但這也沒有幫助。除了在控件的負載中實例化IoC之外，我幾乎不做任何代碼更改，但是我也完全刪除了這些代碼，但無濟於事。

任何人有任何這個問題的經驗？

編輯 - 請注意，如果我添加一個新的用戶控件絕對沒有自定義，並嘗試查看它，我得到同樣的錯誤。

編輯2 - 嘗試「附加到進程」，當我嘗試重新加載設計器時，它沒有做任何事情。

Answer 1

最後在注意到我的其他同事可以看到控件就好了之後發現了它。

在這種情況下的答案似乎是，我的視覺工作室仍在第一版，並需要更新到版本4.所以如果一切都失敗了，而其他人遇到這個問題，下載最新的Visual Studio補丁和啓動它。我很確定它什麼時候安裝完成，它會再次運行。

Answer 2

其中一個原因可能是你的一些靜態資源的結合對象，它是暫時的空

可能例如結合RowData.Row.Property其中row是另一種資源，這是當前行設計時間爲空。

更好的方法是綁定到RowData.Row與轉換器

public object Convert(object value, Type targetType, object parameter, 
        System.Globalization.CultureInfo culture)   
{ 
    if (value is MyContentType) 
    { 
     return (value as MyContentType).Property 
    } 
    else 
    { 
     return defaultValue // this value is valid for wpf control property 
    } 

}   

其他原因可能是你的一些轉換器或TemplateSelectors不會對空

可能是別的東西查詢來電價值但我不知道....

Answer 3

這是Visual Studio在創建不正確的中間文件時的錯誤。只重建所有項目可能無法解決問題。

試試這個，

1. 關閉的Visual Studio。
2. 刪除'obj'文件夾。
3. 重新打開Visual Studio。
4. 重建所有項目。

祝你好運！