How do you cancel the closing operation of ToolWindowPane or Visual Studio IDE through VSPackage?

Question

I have VSPackagewith a dockable tool window containing form data. If there are unsaved changes in this form, I would like to cancel closing the tool window and the IDE visual studio if the user clicks the "Cancel" button when saving changes before closing. I can run a save test on close, but I don't see any event handler methods or other parameters to actually close the close.

Below is a snippet from the package:

    private DTE2 _applicationObject = null;
    ///--------------------------------------------------------------------------------
    /// <summary>This property gets the visual studio IDE application object.</summary>
    ///--------------------------------------------------------------------------------
    public DTE2 ApplicationObject
    {
        get
        {
            if (_applicationObject == null)
            {
                // Get an instance of the currently running Visual Studio IDE
                DTE dte = (DTE)GetService(typeof(DTE));
                _applicationObject = dte as DTE2;
            }
            return _applicationObject;
        }
    }
    ///--------------------------------------------------------------------------------
    /// <summary>
    /// Initialization of the package; this method is called right after the package is sited, so this is the place
    /// where you can put all the initilaization code that rely on services provided by VisualStudio.
    /// </summary>
    ///--------------------------------------------------------------------------------
    protected override void Initialize()
    {
        Trace.WriteLine(string.Format(CultureInfo.CurrentCulture, "Entering Initialize() of: {0}", this.ToString()));
        base.Initialize();

        // add the event handlers
        if (ApplicationObject != null)
        {
            // wire up window events
            PackageWindowEvents = (WindowEvents)ApplicationObject.Events.get_WindowEvents(null);
            PackageWindowEvents.WindowClosing += new _dispWindowEvents_WindowClosingEventHandler(PackageWindowEvents_WindowClosing);

            // wire up solution events
            PackageSolutionEvents = ApplicationObject.Events.SolutionEvents;
            PackageSolutionEvents.Opened += new _dispSolutionEvents_OpenedEventHandler(CheckOpenCurrentSolution);

            // wire up DTE events
            PackageDTEEvents = ApplicationObject.Events.DTEEvents;
            PackageDTEEvents.OnBeginShutdown += new _dispDTEEvents_OnBeginShutdownEventHandler(HandleVisualStudioShutdown);
        }
    }

    void PackageWindowEvents_WindowClosing(Window window)
    {
        // handle save/cancel scenarios
    }

And some commercials from ToolWindowPanethat implement IVsWindowFrameNotify3:

    protected override void OnClose()
    {
        base.OnClose();
    }
    public int OnClose(ref uint pgrfSaveOptions)
    {
        return (int)__FRAMECLOSE.FRAMECLOSE_PromptSave;
    }

OnClose WindowClosing , . ? , ?

Answer 1

, ( Chicobo msdn ).

• ToolWindowPane IVsWindowFrameNotify2, OnClose.

• , :

  public int OnClose(ref uint pgrfSaveOptions)
  {
      // Check if your content is dirty here, then
  
      // Prompt a dialog
      MessageBoxResult res = MessageBox.Show("This Document has been modified. Do you want to save the changes ?",
                    "Unsaved changes", MessageBoxButton.YesNoCancel, MessageBoxImage.Warning);
      // If the users wants to save
      if (res == MessageBoxResult.Yes)
      {
          // Handle with your "save method here"
      }
  
      if (res == MessageBoxResult.Cancel)
      {
          // If "cancel" is clicked, abort the close
          return VSConstants.E_ABORT;
      }
  
      // Else, exit
      return VSConstants.S_OK;
  }
  

Answer 2

, , IDE Visual Studio VsPackage:

    protected override int QueryClose(out bool pfCanClose)
    {
        pfCanClose = false;
        return VSConstants.S_OK;
    }

.