Databases
StackOverflow2013
Postsdbo
PO.NET Runtime exception caused by thread unhandled exception
 

Note that there are some explanatory texts on larger screens.

plurals
  1. PO.NET Runtime exception caused by thread unhandled exception
    primarykey
    data
    text
    <p>I have an <code>Async</code> method that closes some browser popups.</p> <p>Some times the application crashes upon exit with a <code>.NET Runtime</code> error (<strong>mscorwks.dll</strong> with exception code <strong>0xc0000005</strong>). I suspect it happends when the <code>Thread</code> is forced to terminate, because I can't see the logged "Thread exit" line. Could it be the code inside the <code>ExtendedIeBrowser</code> that throws an <code>unhandled exception</code>?</p> <p>You can find the source code below.</p> <pre><code>internal void KeepAliveAsync() { PageController controller = new PageController(); controller.Initialize(siteWebBrowser); var thread = new Thread(() =&gt; { _logger.Debug("Thread start - KeepAliveAsync"); try { while (!Program.ShouldAbortBackgroundOperations()) { try { if (controller.TryCloseTimeoutWarningPopup()) { _logger.Info("KeepAliveAsync: Closed popup successfully"); } Thread.Sleep(5000); } catch (Exception ex) { _logger.ErrorException("KeepAliveAsync", ex); } } } catch (Exception ex) { _logger.ErrorException("KeepAliveAsync", ex); } _logger.Debug("Thread exit - KeepAliveAsync"); }); thread.Name = "KeepAliveAsync"; thread.IsBackground = true; thread.SetApartmentState(ApartmentState.STA); thread.Start(); } </code></pre> <p>The <code>PageController</code> uses this class:</p> <pre><code>public class ExtendedIeBrowser : IE { private IntPtr hwnd; private static Logger _logger = LogManager.GetCurrentClassLogger(); public ExtendedIeBrowser(WebBrowser webBrowserControl) : base(webBrowserControl.ActiveXInstance, false) { } public void Initialize(WebBrowser webBrowserControl) { hwnd = webBrowserControl.FindForm().Handle; // Start the dialog watcher or else the browser won't be able to attach the handler. StartDialogWatcher(); } public override IntPtr hWnd { get { return hwnd; } } protected override void Dispose(bool disposing) { hwnd = IntPtr.Zero; base.Dispose(disposing); } } </code></pre> <p>And this is:</p> <pre><code> internal static bool ShouldAbortBackgroundOperations() { bool should = true; try { should &amp;= Application.OpenForms.Cast&lt;Form&gt;().Count(f =&gt; f.ShowInTaskbar) == 0; // at least one form is shown in the taskbar } catch (Exception ex) { _logger.ErrorException("ShouldAbortBackgroundOperations", ex); should = false; } return should; } </code></pre> <p>The method that closes the popup(literally it's a div inside a web page):</p> <pre><code> internal bool TryCloseTimeoutWarningPopup() { bool success = false; try { Div glassPane = Browser.Div(Find.ByClass(PageConstants.ModalGlassPaneClass)); if (glassPane.Exists) // there is a popup { Div parent = (Div)glassPane.Parent; if (parent.InnerHtml.Contains(PageConstants.WarningLoggingOutPrimaryKeyword)) // correct content on popup { WatiN.Core.Button button = parent.Divs[0].Buttons[0]; ClickOnElement(button); success = true; } } } catch (Exception ex) { _logger.ErrorException("CloseTimeoutWarningPopup", ex); throw; } return success; } </code></pre> <p>What if the program is closed after the Abort checking and CloseTimeoutWarningPopup() is executed? I noticed that at some point after I closed the app, the <code>if (glassPane)</code> row was waiting for the element to show up and tried to access a disposed object. Could it be that object's memory address no longer available and therefore denied?</p>
    singulars
    1. PO
      singulars
      1. PTAnswer
    1. This table or related slice is empty.
    1. PTQuestion
    1. USiCantSeeSharp
    1. USiCantSeeSharp
    plurals
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. PO
      singulars
      1. PTAnswer
    1. VO
      singulars
      1. PO.NET Runtime exception caused by thread unhandled exception
      1. This table or related slice is empty.
      1. VTUpMod
    2. VO
      singulars
      1. PO.NET Runtime exception caused by thread unhandled exception
      1. This table or related slice is empty.
      1. VTUpMod
    1. COI guess you get a ThreadAbortException? This happens if someone (forcibly) stops your thread. You could use a ManualResetEvent (or something) to savely stop your thread. You could also add an eventhandler to the Current's Appdomain UnhandledException event and log it there (but depending on the error it may not be called).
      singulars
      1. PO.NET Runtime exception caused by thread unhandled exception
      1. USBernhard Kircher
    2. COThe log doesn't contain any exception at all. I do have an UnhandledExceptionHandler in the Program.cs, but it hasn't logged anything. ManualResetEvent might be nice, I need to see if it really helps with this situation.
      singulars
      1. PO.NET Runtime exception caused by thread unhandled exception
      1. USiCantSeeSharp
    3. COI think you need to stop the KeepAlyveAsync thread in the ExtendedIeBrowser's dispose method and wait for it to exit (or at least give it the chance to finish). Otherwise the thread may still run and access already disposed data (I guess, because I am not quite sure I understand your code example). You could use a ResetEvent in the backgroundthread to check if it has been "Set" in the Dispose.
      singulars
      1. PO.NET Runtime exception caused by thread unhandled exception
      1. USBernhard Kircher
 

Querying!

 
Guidance
A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

SQuiL has stopped working due to an internal error.

If you are curious you may find further information in the browser console, which is accessible through the devtools (F12).

Reload