的Parallel.For及的ListCollectionView

Question

我有一個listcollectionview，我想遍歷使用Parallel.For

到目前爲止我有：

 public void HighlightLoggingLvl(
     LoggingLvl.ELoggingLvl loggingLvl, bool ebool) { 
     Parallel.For(0, HighlighterCollectionView.Count, i => { 
       Log4NetLog cC = 
        HighlighterCollectionView.GetItemAt(i) as 
        Log4NetLog; 

       if (cC != null && 
        cC.MyLoggingLvl.EloggingLvl == loggingLvl) { 
         if (ebool) { 
          cC.LogColour.SetColor(cC.MyLoggingLvl); 
          } else { 
            cC.LogColour.Colour = Colors.Transparent; 
          } 
       } 
     }); 
     HighlighterCollectionView.Refresh(); 
    } 

即時得到以下錯誤：

A first chance exception of type 'System.InvalidOperationException' occurred in  WindowsBase.dll 
A first chance exception of type 'System.InvalidOperationException' occurred in  WindowsBase.dll 
A first chance exception of type 'System.InvalidOperationException' occurred in mscorlib.dll 
A first chance exception of type 'System.InvalidOperationException' occurred in mscorlib.dll 
A first chance exception of type 'System.AggregateException' occurred in mscorlib.dll 
A first chance exception of type 'System.AggregateException' occurred in mscorlib.dll 
A first chance exception of type 'System.Reflection.TargetInvocationException' occurred in mscorlib.dll 
System.Windows.Data Error: 8 : Cannot save value from target back to source. BindingExpression:Path=Log4NetSearchEngineCompassLogView.Log4NetHighlighter.IsAllHighlighterEnable; DataItem='CompassLogView' (HashCode=57871897); target element is 'CheckBox' (Name=''); target property is 'IsChecked' (type 'Nullable`1') AggregateException:'System.AggregateException: One or more errors occurred. ---> System.InvalidOperationException: The calling thread cannot access this object because a different thread owns it. 
at System.Windows.Threading.Dispatcher.VerifyAccess() 
at System.Windows.Threading.DispatcherObject.VerifyAccess() 
at System.Windows.Data.CollectionView.VerifyRefreshNotDeferred() 
at System.Windows.Data.ListCollectionView.GetItemAt(Int32 index) 
at LogViewerViewModel.tools.highlighters.Log4NetHighlighter.<>c__DisplayClass1.<HighlightLoggingLvl>b__0(Int32 i) in c:\Users\Reza\Documents\Visual Studio 2012\Projects\Pallas informatik\LogViewerV1\LogViewerViewModel\src\tools\highlighters\Log4NetHighlighter.cs:line 193 
at System.Threading.Tasks.Parallel.<>c__DisplayClassf`1.<ForWorker>b__c() 
at System.Threading.Tasks.Task.InnerInvoke() 
at System.Threading.Tasks.Task.InnerInvokeWithArg(Task childTask) 
at System.Threading.Tasks.Task.<>c__DisplayClass10.<ExecuteSelfReplicating>b__f(Object param0) 
--- End of inner exception stack trace --- 
at System.Threading.Tasks.Task.ThrowIfExceptional(Boolean includeTaskCanceledExceptions) 
at System.Threading.Tasks.Task.Wait(Int32 millisecondsTimeout, CancellationToken cancellationToken) 
    at System.Threading.Tasks.Task.Wait() 
    at System.Threading.Tasks.Parallel.ForWorker[TLocal](Int32 fromInclusive, Int32 toExclusive, ParallelOptions parallelOptions, Action`1 body, Action`2 bodyWithState, Func`4 bodyWithLocal, Func`1 localInit, Action`1 localFinally) 
    at System.Threading.Tasks.Parallel.For(Int32 fromInclusive, Int32 toExclusive, Action`1 body) 
     at LogViewerViewModel.tools.highlighters.Log4NetHighlighter.HighlightLoggingLvl(ELoggingLvl loggingLvl, Boolean ebool) in c:\Users\Reza\Documents\Visual Studio 2012\Projects\Pallas informatik\LogViewerV1\LogViewerViewModel\src\tools\highlighters\Log4NetHighlighter.cs:line 190 
at LogViewerViewModel.tools.highlighters.Log4NetHighlighter.set_IsDebugHighlighterEnable(Boolean value) in c:\Users\Reza\Documents\Visual Studio 2012\Projects\Pallas informatik\LogViewerV1\LogViewerViewModel\src\tools\highlighters\Log4NetHighlighter.cs:line 59 
    at LogViewerViewModel.tools.highlighters.Log4NetHighlighter.set_IsAllHighlighterEnable(Boolean value) in c:\Users\Reza\Documents\Visual Studio 2012\Projects\Pallas informatik\LogViewerV1\LogViewerViewModel\src\tools\highlighters\Log4NetHighlighter.cs:line 39 
---> (Inner Exception #0) System.InvalidOperationException: The calling thread cannot access this object because a different thread owns it. 
    at System.Windows.Threading.Dispatcher.VerifyAccess() 
    at System.Windows.Threading.DispatcherObject.VerifyAccess() 
    at System.Windows.Data.CollectionView.VerifyRefreshNotDeferred() 
    at System.Windows.Data.ListCollectionView.GetItemAt(Int32 index) 
    at LogViewerViewModel.tools.highlighters.Log4NetHighlighter.<>c__DisplayClass1.<HighlightLoggingLvl>b__0(Int32 i) in c:\Users\Reza\Documents\Visual Studio 2012\Projects\Pallas informatik\LogViewerV1\LogViewerViewModel\src\tools\highlighters\Log4NetHighlighter.cs:line 193 
    at System.Threading.Tasks.Parallel.<>c__DisplayClassf`1.<ForWorker>b__c() 
    at System.Threading.Tasks.Task.InnerInvoke() 
    at System.Threading.Tasks.Task.InnerInvokeWithArg(Task childTask) 
    at System.Threading.Tasks.Task.<>c__DisplayClass10.<ExecuteSelfReplicating>b__f(Object param0)<--- 

如何我可以修復這個問題嗎？ （代碼示例將是巨大的）

Answer 1

你應該調用在UI線程的操作。

參見分派器類與invoke method

或 Understanding dispatcher in WPF

Answer 2

不能使用並行處理來更新UI元素。只有您的應用程序的主線程才具有對用戶界面的訪問權限。可以在複選框上調用Invoke，但對於正在進行的工作，並行執行操作有什麼意義？它不會給你買任何表演。

我建議使用只是一個普通的for循環而不是Parallel.For。