VS2008 XAML设计异常使用来自ResourceDictionary的默认样式时“键不能为空”

我使用一个共享的资源字典定义默认的样式，并具有在Visual Studio 2008中使用XAML设计主要冲突中的关键不能为空出现的所有尝试，以显示XAML设计视图。

字典合并到App.xaml中（供所有的窗口一起使用），并具有许多样式设置控件的缺省值，所以它们被定义为如下所示不用钥匙 。 如果添加X：关键属性的样式，他们不再默认应用。 我不希望有明确的把风格条款上的每个控件，但它看起来像我可能会。

<ResourceDictionary xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
    <Style x:Key="windowStyle" TargetType="{x:Type Window}">
        <Setter Property="Background" Value="LightGray" />
    </Style>
    <Style TargetType="{x:Type TextBox}">
        <Setter Property="Background" Value="AliceBlue" />
        <Setter Property="Height" Value="23" />
    </Style>
</ResourceDictionary>

与堆栈完整的异常错误信息：

Key cannot be null.
Parameter name: key
   at System.Collections.Hashtable.get_Item(Object key)
   at MS.Internal.Xaml.AssemblyNode.For(Assembly assembly, Boolean includeInternal)
   at MS.Internal.Xaml.ReflectionProjectNode.LoadAssembly(AssemblyName name, Boolean includeInternal)
   at MS.Internal.Xaml.ReflectionProjectNode.BuildAssemblies()
   at MS.Internal.Xaml.ReflectionProjectNode.BuildSubsumption()
   at MS.Internal.Xaml.ReflectionProjectNode.SubsumingNamespace(Identifier identifier)
   at MS.Internal.Xaml.XmlElement.BuildScope(PrefixScope parentScope, IParseContext context)
   at MS.Internal.Xaml.XmlElement.FindElementType(PrefixScope parentScope, IParseContext context)
   at MS.Internal.DocumentTrees.Markup.XamlSourceDocument.get_RootType()
   at Microsoft.Windows.Design.Documents.Trees.MarkupDocumentTreeManager.get_RootType()
   at Microsoft.Windows.Design.Documents.MarkupDocumentManager.CalculateLoadErrorState()
   at Microsoft.Windows.Design.Documents.MarkupDocumentManager.get_LoadState()
   at MS.Internal.Host.PersistenceSubsystem.Load()
   at MS.Internal.Host.Designer.Load()
   at MS.Internal.Designer.VSDesigner.Load()
   at MS.Internal.Designer.VSIsolatedDesigner.VSIsolatedView.Load()
   at MS.Internal.Designer.VSIsolatedDesigner.VSIsolatedDesignerFactory.Load(IsolatedView view)
   at MS.Internal.Host.Isolation.IsolatedDesigner.BootstrapProxy.LoadDesigner(IsolatedDesignerFactory factory, IsolatedView view)
   at MS.Internal.Host.Isolation.IsolatedDesigner.BootstrapProxy.LoadDesigner(IsolatedDesignerFactory factory, IsolatedView view)
   at MS.Internal.Host.Isolation.IsolatedDesigner.Load()
   at MS.Internal.Designer.DesignerPane.LoadDesignerView()

Answer 1:

我不知道为什么它会需要一个关键，但你可以尝试以下方法

<Style x:Key="{x:Type TextBox}" TargetType="{x:Type TextBox}">

文章来源: VS2008 XAML Designer exception “Key cannot be null” when using default styles from a ResourceDictionary