Control.Invoke上的AccessViolationException

Question

我的设置如下。我有一个带有Log属性的UI线程，用于更新RichTextBox。我有一个非UI线程填充Log属性。非UI线程由Timer控制。我还在UI中有一个更新Log属性的Button。 LogPresenter只是一个格式化消息并将其发送到Log Property的类。

当我更新RichTextBox上的SelectedText属性时，我随机收到一个AccessViolationException。这里是相关的代码

public static class ThreadHelpers
{
    public static void InvokeIfRequired(this Control c, Action a)
    {
        if (c.InvokeRequired)
            c.Invoke(a);
        else
            a();
    }
}

public string Log
{
    set
    {
        lock (value)
        {
            richLog.InvokeIfRequired(() => OnLogMessage(value));
        }                
    }
}

[HandleProcessCorruptedStateExceptions]
private void OnLogMessage(string message)
{
    try
    {
        richLog.SelectionStart = richLog.Text.Length;

        var selection = message.Split('-');
        var loggingLevel = selection[0].Trim();

        switch (loggingLevel)
        {
            case "Information":
                richLog.SelectionColor = Color.SteelBlue;
                break;
            case "Warning":
                richLog.SelectionColor = Color.Goldenrod;
                break;
            case "Error":
                richLog.SelectionColor = Color.DarkRed;
                break;
            case "SuccessAudit":
                richLog.SelectionColor = Color.DarkOliveGreen;
                break;
            case "FailureAudit":
                richLog.SelectionColor = Color.OrangeRed;
                break;
            default:
                richLog.SelectionColor = Color.Silver;
                break;
        }

        richLog.SelectedText = message;
        ScrollToBottom();
     }
     catch (Exception ex)
     {
        // The lines below just cause cascading fail so I took them out.
        //_logPresenter.Fail("Failed to write Log: {0}", message);
        //_logPresenter.Error("{0}" + Environment.NewLine + "StackTrace: {0}", ex.Message, ex.StackTrace);
     }
 }

我得到的确切错误是这样的： System.AccessViolationException

尝试读取或写入受保护的内存。这通常表明其他内存已损坏。

   at System.Windows.Forms.UnsafeNativeMethods.CallWindowProc(IntPtr wndProc, IntPtr hWnd, Int32 msg, IntPtr wParam, IntPtr lParam)
   at System.Windows.Forms.NativeWindow.DefWndProc(Message& m)
   at System.Windows.Forms.Control.DefWndProc(Message& m)
   at System.Windows.Forms.Control.WndProc(Message& m)
   at System.Windows.Forms.TextBoxBase.WndProc(Message& m)
   at System.Windows.Forms.RichTextBox.WndProc(Message& m)
   at System.Windows.Forms.Control.ControlNativeWindow.OnMessage(Message& m)
   at System.Windows.Forms.Control.ControlNativeWindow.WndProc(Message& m)
   at System.Windows.Forms.NativeWindow.DebuggableCallback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)
   at System.Windows.Forms.UnsafeNativeMethods.SendMessage(HandleRef hWnd, Int32 msg, Int32 wParam, EDITSTREAM lParam)
   at System.Windows.Forms.RichTextBox.StreamIn(Stream data, Int32 flags)
   at System.Windows.Forms.RichTextBox.StreamIn(String str, Int32 flags)
   at System.Windows.Forms.RichTextBox.set_SelectedText(String value)
   at Namespace.InteractiveServiceForm.OnLogMessage(String message) in c:\projects\Namespace\InteractiveServiceForm.cs:line 127

我尝试了锁，但它没有帮助任何建议将不胜感激。该应用程序现在只是悬挂UI。