XamlParseException停止项目

Question

我正在使用“Microsoft VS C# 2010 Step by Step”这本书学习任务2010，该书的第27章介绍了任务并行库。当我运行提供的'GraphDemo‘项目时，我得到一个XamlParseException错误。我在同一个异常上检查了这个站点上的几个线程，并设法将内部异常深入到加载PerformanceCounter失败的原因。由于担心系统的.NET Framework4安装损坏，我将其修复为原始状态，但错误仍然存在。奇怪的是，这本书的其他读者都没有抱怨过这个问题；在我写信给出版商后，作者要求我给他发送一个项目的zipfile，他声称它在他的机器上运行得很好。在第27章中还有其他七个项目，它们都在我的系统上抛出了相同的错误。

下面是生成的异常的全文：

System.Windows.Markup.XamlParseException was unhandled
  Message='The invocation of the constructor on type 'GraphDemo.GraphWindow' that matches the specified binding constraints threw an exception.' Line number '3' and line position '5'.
  Source=PresentationFramework
  LineNumber=3
  LinePosition=5
  StackTrace:
       at System.Windows.Markup.XamlReader.RewrapException(Exception e, IXamlLineInfo lineInfo, Uri baseUri)
       at System.Windows.Markup.WpfXamlLoader.Load(XamlReader xamlReader, IXamlObjectWriterFactory writerFactory, Boolean skipJournaledProperties, Object rootObject, XamlObjectWriterSettings settings, Uri baseUri)
       at System.Windows.Markup.WpfXamlLoader.LoadBaml(XamlReader xamlReader, Boolean skipJournaledProperties, Object rootObject, XamlAccessLevel accessLevel, Uri baseUri)
       at System.Windows.Markup.XamlReader.LoadBaml(Stream stream, ParserContext parserContext, Object parent, Boolean closeStream)
       at System.Windows.Application.LoadBamlStreamWithSyncInfo(Stream stream, ParserContext pc)
       at System.Windows.Application.LoadComponent(Uri resourceLocator, Boolean bSkipJournaledProperties)
       at System.Windows.Application.DoStartup()
       at System.Windows.Application.<.ctor>b__1(Object unused)
       at System.Windows.Threading.ExceptionWrapper.InternalRealCall(Delegate callback, Object args, Int32 numArgs)
       at MS.Internal.Threading.ExceptionFilterHelper.TryCatchWhen(Object source, Delegate method, Object args, Int32 numArgs, Delegate catchHandler)
       at System.Windows.Threading.DispatcherOperation.InvokeImpl()
       at System.Windows.Threading.DispatcherOperation.InvokeInSecurityContext(Object state)
       at System.Threading.ExecutionContext.runTryCode(Object userData)
       at System.Runtime.CompilerServices.RuntimeHelpers.ExecuteCodeWithGuaranteedCleanup(TryCode code, CleanupCode backoutCode, Object userData)
       at System.Threading.ExecutionContext.RunInternal(ExecutionContext executionContext, ContextCallback callback, Object state)
       at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean ignoreSyncCtx)
       at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
       at System.Windows.Threading.DispatcherOperation.Invoke()
       at System.Windows.Threading.Dispatcher.ProcessQueue()
       at System.Windows.Threading.Dispatcher.WndProcHook(IntPtr hwnd, Int32 msg, IntPtr wParam, IntPtr lParam, Boolean& handled)
       at MS.Win32.HwndWrapper.WndProc(IntPtr hwnd, Int32 msg, IntPtr wParam, IntPtr lParam, Boolean& handled)
       at MS.Win32.HwndSubclass.DispatcherCallbackOperation(Object o)
       at System.Windows.Threading.ExceptionWrapper.InternalRealCall(Delegate callback, Object args, Int32 numArgs)
       at MS.Internal.Threading.ExceptionFilterHelper.TryCatchWhen(Object source, Delegate method, Object args, Int32 numArgs, Delegate catchHandler)
       at System.Windows.Threading.Dispatcher.InvokeImpl(DispatcherPriority priority, TimeSpan timeout, Delegate method, Object args, Int32 numArgs)
       at MS.Win32.HwndSubclass.SubclassWndProc(IntPtr hwnd, Int32 msg, IntPtr wParam, IntPtr lParam)
       at MS.Win32.UnsafeNativeMethods.DispatchMessage(MSG& msg)
       at System.Windows.Threading.Dispatcher.PushFrameImpl(DispatcherFrame frame)
       at System.Windows.Threading.Dispatcher.PushFrame(DispatcherFrame frame)
       at System.Windows.Application.RunDispatcher(Object ignore)
       at System.Windows.Application.RunInternal(Window window)
       at System.Windows.Application.Run(Window window)
       at System.Windows.Application.Run()
       at GraphDemo.App.Main() in E:\IT Books\Source Code Projects\Microsoft Visual C# 2010 Step By Step\Chapter 27\GraphDemo\GraphDemo\obj\x86\Debug\App.g.cs:line 0
       at System.AppDomain._nExecuteAssembly(RuntimeAssembly assembly, String[] args)
       at System.AppDomain.ExecuteAssembly(String assemblyFile, Evidence assemblySecurity, String[] args)
       at Microsoft.VisualStudio.HostingProcess.HostProc.RunUsersAssembly()
       at System.Threading.ThreadHelper.ThreadStart_Context(Object state)
       at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean ignoreSyncCtx)
       at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
       at System.Threading.ThreadHelper.ThreadStart()
  InnerException: System.InvalidOperationException
       Message=Cannot load Counter Name data because an invalid index '' was read from the registry.
       Source=System
       StackTrace:
            at System.Diagnostics.PerformanceCounterLib.GetStringTable(Boolean isHelp)
            at System.Diagnostics.PerformanceCounterLib.get_NameTable()
            at System.Diagnostics.PerformanceCounterLib.get_CategoryTable()
            at System.Diagnostics.PerformanceCounterLib.CounterExists(String category, String counter, Boolean& categoryExists)
            at System.Diagnostics.PerformanceCounterLib.CounterExists(String machine, String category, String counter)
            at System.Diagnostics.PerformanceCounter.InitializeImpl()
            at System.Diagnostics.PerformanceCounter..ctor(String categoryName, String counterName, String instanceName, Boolean readOnly)
            at System.Diagnostics.PerformanceCounter..ctor(String categoryName, String counterName)
            at GraphDemo.GraphWindow..ctor() in E:\IT Books\Source Code Projects\Microsoft Visual C# 2010 Step By Step\Chapter 27\GraphDemo\GraphDemo\GraphWindow.xaml.cs:line 25
       InnerException: 

And this is the code pinpointed by the inner exception:

    public GraphWindow()
    {
        InitializeComponent();
        PerformanceCounter memCounter = new PerformanceCounter("Memory", "Available Bytes");
        availableMemorySize = Convert.ToUInt64(memCounter.NextValue());
        this.pixelWidth = (int)availableMemorySize / 20000;
        if (this.pixelWidth < 0 || this.pixelWidth > 15000)
        this.pixelWidth = 15000;
        this.pixelHeight = (int)availableMemorySize / 40000;
        if (this.pixelHeight < 0 || this.pixelHeight > 7500)
        this.pixelHeight = 7500;
    }

第25行是初始化memCounter的那一行。

我将感谢所有我能得到的帮助。

Answer 1

您很有可能在针对4.0框架时引用.Net 2.0应用程序。尝试将useLegacyV2RuntimeActivationPolicy="true"添加到配置文件中：

<?xml version="1.0" encoding="utf-8" ?>
<configuration>
  <startup useLegacyV2RuntimeActivationPolicy="true">
    <supportedRuntime version="v4.0"/>
  </startup>
</configuration>

Answer 2

我也遇到了同样的问题，下面是我是如何解决的。基本上，您的性能计数器列表已损坏。http://blogs.technet.com/b/yongrhee/archive/2009/10/06/how-to-rebuild-performance-counters-on-windows-vista-server2008-7-server2008r2.aspx

要解决此问题，请以管理员身份运行CMD，然后在命令提示符下输入：

C:\Windows\System32\lodctr /r

性能计数器将从头开始重建。