Cannot seem to Cancel EXCEL App Right Click Event using C#

[Guest]

I am trying to use Excel from C# and need to disable the menu that appears when clicking the right mouse button on a cell.

I am trying to do this using the Excel.AppEvents_SheetBeforeRightClickEventHandler from my C# WinForm application.

I have a MessageBox that pops up that proves my event handler actually fires via my delegate but after setting the "Cancel" variable to "true" it has no effect for me. The Excel RMB menu appears when it should not. The Cancel parameter is declared as "ref bool".

I am wondering if there is a problem with the marshalling of this variable in the Office PIA which I am using. I would be happy to send code that demos my problem. Can someone please let me know if they can make it work ?

By the way I have already written some VB6 code that works fine and VBA code in an Excel Workbook that also works just fine as well. Both disable the menu as I require when I set "Cancel" to "True". The problem is that I need to do this from a C# application.

Can anyone shed some light on this at all ?

I am using...

Microsoft Excel 2002 (10.4302.4219) SP-2
Visual Studio 2003 v7.1.3088
Microsoft .NET Framework 1.1 v1.1.4322

I obtained the Office XP Primary Interop Assemblies from the following link

http://www.microsoft.com/downloads/...1e-3060-4f71-a6b4-01feba508e52&displaylang=en

 

[Guest]

I don't believe you can disable the right click on the activesheet. If you set the AllowPropertyToolbox to false, it disables the Property Toolbox on the right click menu. There is no other property that can be set. The list of properties is:

ActiveCell ActivePane ActiveSheet
AllowPropertyToolbox AutoFit BuildNumber
CSVData CSVURL CanUndo
Cells Columns Constants
DataType Dirty DisplayColHeaders
DisplayGridlines DisplayHorizontalScrollBar DisplayPropertyToolbox
DisplayRowHeaders DisplayTitleBar DisplayToolbar
DisplayVerticalScrollBar EnableAutoCalculate EnableEvents
EnableUndo HTMLData HTMLURL
MajorVersion MaxHeight MaxWidth
MinorVersion MoveAfterReturn MoveAfterReturnDirection
Range RevisionNumber RightToLeft
Rows ScreenUpdating Selection
TitleBar Version ViewableRange

I can't see that there is a right click event.The list of events is:

BeforeCommand Calculate CancelEdit
Change Click Command
DblClick EndEdit KeyDown
KeyPress KeyUp MouseDown
MouseOut MouseOver MouseUp
SelectionChange SelectionChanging StartEdit
ViewChange

Like you, I think the OWC PIA is screwed up. Can you help with my post "OWC Web Component Spreadsheet: C#" in this news group?

 

[Dave Peterson]

I think you're speaking the Greek here!

But I can disable the rightclick option on a worksheet by disabling the "Cell"
commandbar.

Maybe it'll work for you:

Dim myIndex As Long
myIndex = Application.CommandBars("cell").Index
Application.CommandBars(myIndex).Enabled = False
Application.CommandBars(myIndex + 3).Enabled = False

The +3 refers to the "cell" commandbar when you're in View|PageBreak Preview
mode.

(Don't forget to turn it back to True when you're done. This setting will be
kept the next time excel opens!)

 

[Peter Huang]

Hi Snark,

There is an known issue in the Office XP PIA which will cause the problem
and the problem has been fixed in the Office 2003 PIA.
Now to workaround the problem, I think we can try to sink the problem
ourselves.

private UCOMIConnectionPoint m_oConnectionPoint;
private int m_Cookie;
private Excel.ApplicationClass exApp;


private void button1_Click(object sender, System.EventArgs e) //sink the
events
{
// QI for IConnectionPointContainer.
UCOMIConnectionPointContainer oConnPointContainer =
(UCOMIConnectionPointContainer)exApp;
// Get the GUID of the EApplication interface.
Guid guid=typeof(Excel.AppEvents).GUID;
// Find the connection point.
oConnPointContainer.FindConnectionPoint(ref guid,out m_oConnectionPoint);
// Call Advise to sink up the connection.
m_oConnectionPoint.Advise(this,out m_Cookie);
}
private void button2_Click(object sender, System.EventArgs e)
{
m_oConnectionPoint.Unadvise(m_Cookie);
System.Runtime.InteropServices.Marshal.ReleaseComObject(exApp);
GC.Collect();
}
[DispId(1560)]
public void SheetBeforeRightClick(object Sh , object Target ,ref bool
Cancel) //Event handler function
{
Cancel = true;
}
private void Form1_Load(object sender, System.EventArgs e)
{
//Create an instance of Excel .
exApp = new Excel.ApplicationClass();
// Show Excel to the user.
exApp.Visible = true;
}
How To Handle PowerPoint Events With Visual C# .NET
http://support.microsoft.com/default.aspx?scid=KB;EN-US;308825

HOW TO: Establish a COM Event Sink with Return Values in the .NET Framework
by Using Visual Basic .NET (810228)
http://support.microsoft.com/default.aspx?scid=KB;EN-US;810228

Best regards,

Peter Huang
Microsoft Online Partner Support

Get Secure! - www.microsoft.com/security
This posting is provided "AS IS" with no warranties, and confers no rights.

 

[Guest]

Peter,

Many thanks - this works! I have put your code in a simple WinForm app and it works just fine. I am now trying to understand why the technique which I followed based on KB article 830519 does not work. I posted my code on another thread so here is a link to it

http://msdn.microsoft.com/newsgroup...724d0e27#b9ab348d-0491-44a2-a284-68f3724d0e27

Any ideas why your code works but my Q830519 styled solution does not ?

Nick

 

[Peter Huang]

Hi Nick,

Now I am researching the issue, and I will get back here and update you
with new information ASAP.

Best regards,

Peter Huang
Microsoft Online Partner Support

Get Secure! - www.microsoft.com/security
This posting is provided "AS IS" with no warranties, and confers no rights.

 

[Peter Huang]

Hi Nick,

Based on my research, we need to specified the attribute as below.
[ClassInterface(ClassInterfaceType.None)]
public class Excel10EventHelper : IExcelAppEvents10, IDisposable

So that we can guarantee that there is no default interface generate for
Excel10EventHelper class.
You may have a try and let me know the result.

Best regards,

Peter Huang
Microsoft Online Partner Support

Get Secure! - www.microsoft.com/security
This posting is provided "AS IS" with no warranties, and confers no rights.

 

[Guest]

Peter,

What can I say... this solves all my problems. Vary many thanks.

Nick

 

[Guest]

I'm new to VB in excel and am trying to remove the right click menu....I saw
your advice below and tried it out however, when I replace the "Cancel" in
"Worksheet_BeforeRightClick(ByVal Target As Range, Cancel As Boolean)" with
"True" it comes up with a compile error...am I being completely thick?

 

[Bob Phillips]

No, you don't replace Cancel with True, you set it to true

Private Sub Worksheet_BeforeRightClick(ByVal Target As Range, Cancel As
Boolean)
Cancel = True
End Sub


--

HTH

RP
(remove nothere from the email address if mailing direct)

I'm new to VB in excel and am trying to remove the right click menu....I saw
your advice below and tried it out however, when I replace the "Cancel" in
"Worksheet_BeforeRightClick(ByVal Target As Range, Cancel As Boolean)" with
"True" it comes up with a compile error...am I being completely thick?

Specifically you simply set the "Cancel" parameter to "True" inside the
SheetBeforeRightClick event handler. I can do this from VBA in an XLS
workbook and also from VB6 via Ole Automation.something to say but it does not appear to work for Excel. Check out the
post by Chris Peacock titled "Problem implementing connection point sink" in
this newsgroup for a further discussion and some dodgy code by my good self!you set the AllowPropertyToolbox to false, it disables the Property Toolbox
Excel.AppEvents_SheetBeforeRightClickEventHandler from my C# WinForm
application.actually fires via my delegate but after setting the "Cancel" variable to
"true" it has no effect for me. The Excel RMB menu appears when it should
not. The Cancel parameter is declared as "ref bool".variable in the Office PIA which I am using. I would be happy to send code
that demos my problem. Can someone please let me know if they can make it
work ?VBA code in an Excel Workbook that also works just fine as well. Both
disable the menu as I require when I set "Cancel" to "True". The problem is
that I need to do this from a C# application.

 

[Leviatano]

And here is the fixed code...

Question is this... should the Excel10EventHelper class that is inheriting from IExcelAppEvents10 also be inheriting the interfaces [DispId] attributes or not ?

Nick


using System;
using System.Runtime.InteropServices;
using Excel=Microsoft.Office.Interop.Excel;

namespace ExcelAppEvents10
{
[InterfaceType(ComInterfaceType.InterfaceIsIDispatch),
GuidAttribute("00024413-0000-0000-C000-000000000046")]
public interface IExcelAppEvents10
{
[DispId(0x0000061d)] void NewWorkbook(Excel.Workbook Wb);
[DispId(0x00000616)] void SheetSelectionChange(object sh, Excel.Range Target);
[DispId(0x00000617)] void SheetBeforeDoubleClick(object sh, Excel.Range Target, ref bool Cancel);
[DispId(0x00000618)] void SheetBeforeRightClick(object sh, Excel.Range Target, ref bool Cancel);
[DispId(0x00000619)] void SheetActivate(object sh);
[DispId(0x0000061a)] void SheetDeactivate(object sh);
[DispId(0x0000061b)] void SheetCalculate(object sh);
[DispId(0x0000061c)] void SheetChange(object sh, Excel.Range Target);
[DispId(0x0000061f)] void WorkbookOpen(Excel.Workbook Wb);
[DispId(0x00000620)] void WorkbookActivate(Excel.Workbook Wb);
[DispId(0x00000621)] void WorkbookDeactivate(Excel.Workbook Wb);
[DispId(0x00000622)] void WorkbookBeforeClose(Excel.Workbook Wb, ref bool Cancel);
[DispId(0x00000623)] void WorkbookBeforeSave(Excel.Workbook Wb, bool SaveAsUI, ref bool Cancel);
[DispId(0x00000624)] void WorkbookBeforePrint(Excel.Workbook Wb, ref bool Cancel);
[DispId(0x00000625)] void WorkbookNewSheet(Excel.Workbook Wb, object sh);
[DispId(0x00000626)] void WorkbookAddinInstall(Excel.Workbook Wb);
[DispId(0x00000627)] void WorkbookAddinUninstall(Excel.Workbook Wb);
[DispId(0x00000612)] void WindowResize(Excel.Workbook Wb, Excel.Window Wn);
[DispId(0x00000614)] void WindowActivate(Excel.Workbook Wb, Excel.Window Wn);
[DispId(0x00000615)] void WindowDeactivate(Excel.Workbook Wb, Excel.Window Wn);
[DispId(0x0000073e)] void SheetFollowHyperlink(object sh, Excel.Hyperlink Target);
[DispId(0x0000086d)] void SheetPivotTableUpdate(object sh, Excel.PivotTable Target);
[DispId(0x00000870)] void WorkbookPivotTableCloseConnection(Excel.Workbook Wb, Excel.PivotTable Target);
[DispId(0x00000871)] void WorkbookPivotTableOpenConnection(Excel.Workbook Wb, Excel.PivotTable Target);
}

public class Excel10EventHelper : IExcelAppEvents10, IDisposable
{
public Excel10EventHelper()
{
m_oConnectionPoint = null;
m_Cookie = 0;
}

[DispId(0x0000061d)]
public void NewWorkbook(Excel.Workbook Wb)
{System.Diagnostics.Debug.WriteLine("NewWorkbook");}

[DispId(0x00000616)]
public void SheetSelectionChange(object sh, Excel.Range Target)
{System.Diagnostics.Debug.WriteLine("SheetSelectionChange");}

[DispId(0x00000617)]
public void SheetBeforeDoubleClick(object sh, Excel.Range Target, ref bool Cancel)
{System.Diagnostics.Debug.WriteLine("SheetBeforeDoubleClick");}

[DispId(0x00000618)]
public void SheetBeforeRightClick(object sh, Excel.Range Target, ref bool Cancel)
{
System.Diagnostics.Debug.WriteLine("SheetBeforeRightClick");
Cancel = true; // Cancel the right click!
}

[DispId(0x00000619)]
public void SheetActivate(object sh)
{System.Diagnostics.Debug.WriteLine("SheetActivate");}

[DispId(0x0000061a)]
public void SheetDeactivate(object sh)
{System.Diagnostics.Debug.WriteLine("SheetDeactivate");}

[DispId(0x0000061b)]
public void SheetCalculate(object sh)
{System.Diagnostics.Debug.WriteLine("SheetCalculate");}

[DispId(0x0000061c)]
public void SheetChange(object sh, Excel.Range Target)
{System.Diagnostics.Debug.WriteLine("SheetChange");}

[DispId(0x0000061f)]
public void WorkbookOpen(Excel.Workbook Wb)
{System.Diagnostics.Debug.WriteLine("WorkbookOpen");}

[DispId(0x00000620)]
public void WorkbookActivate(Excel.Workbook Wb)
{System.Diagnostics.Debug.WriteLine("WorkbookActivate");}

[DispId(0x00000621)]
public void WorkbookDeactivate(Excel.Workbook Wb)
{System.Diagnostics.Debug.WriteLine("WorkbookDeactivate");}

[DispId(0x00000622)]
public void WorkbookBeforeClose(Excel.Workbook Wb, ref bool Cancel)
{System.Diagnostics.Debug.WriteLine("WorkbookBeforeClose");}

[DispId(0x00000623)]
public void WorkbookBeforeSave(Excel.Workbook Wb, bool SaveAsUI, ref bool Cancel)
{System.Diagnostics.Debug.WriteLine("WorkbookBeforeSave");}

[DispId(0x00000624)]
public void WorkbookBeforePrint(Excel.Workbook Wb, ref bool Cancel)
{System.Diagnostics.Debug.WriteLine("WorkbookBeforePrint");}

[DispId(0x00000625)]
public void WorkbookNewSheet(Excel.Workbook Wb, object sh)
{System.Diagnostics.Debug.WriteLine("WorkbookNewSheet");}

[DispId(0x00000626)]
public void WorkbookAddinInstall(Excel.Workbook Wb)
{System.Diagnostics.Debug.WriteLine("WorkbookAddinInstall");}

[DispId(0x00000627)]
public void WorkbookAddinUninstall(Excel.Workbook Wb)
{System.Diagnostics.Debug.WriteLine("WorkbookAddinUninstall");}

[DispId(0x00000612)]
public void WindowResize(Excel.Workbook Wb, Excel.Window Wn)
{System.Diagnostics.Debug.WriteLine("WindowResize");}

[DispId(0x00000614)]
public void WindowActivate(Excel.Workbook Wb, Excel.Window Wn)
{System.Diagnostics.Debug.WriteLine("WindowActivate");}

[DispId(0x00000615)]
public void WindowDeactivate(Excel.Workbook Wb, Excel.Window Wn)
{System.Diagnostics.Debug.WriteLine("WindowDeactivate");}

[DispId(0x0000073e)]
public void SheetFollowHyperlink(object sh, Excel.Hyperlink Target)
{System.Diagnostics.Debug.WriteLine("SheetFollowHyperlink");}

[DispId(0x0000086d)]
public void SheetPivotTableUpdate(object sh, Excel.PivotTable Target)
{System.Diagnostics.Debug.WriteLine("SheetPivotTableUpdate");}

[DispId(0x00000870)]
public void WorkbookPivotTableCloseConnection(Excel.Workbook Wb, Excel.PivotTable Target)
{System.Diagnostics.Debug.WriteLine("WorkbookPivotTableCloseConnection");}

[DispId(0x00000871)]
public void WorkbookPivotTableOpenConnection(Excel.Workbook Wb, Excel.PivotTable Target)
{System.Diagnostics.Debug.WriteLine("WorkbookPivotTableOpenConnection");}

private UCOMIConnectionPoint m_oConnectionPoint;
private int m_Cookie;
private Excel.ApplicationClass m_xlApp;

public void SetupConnection(Excel.ApplicationClass app)
{
if (m_Cookie != 0) return;

// QI for IConnectionPointContainer.
UCOMIConnectionPointContainer oConnPointContainer = (UCOMIConnectionPointContainer) app;

// GUID of the Excel AppEvents dispinterface.
Guid guid = new Guid("{00024413-0000-0000-C000-000000000046}");
// Guid guid = typeof(Excel.AppEvents).GUID; also works!

// Find the connection point.
oConnPointContainer.FindConnectionPoint(ref guid, out m_oConnectionPoint);

// Call Advise to sink up the connection.
m_oConnectionPoint.Advise(this, out m_Cookie);
}

public void RemoveConnection()
{
if (m_Cookie != 0)
{
m_oConnectionPoint.Unadvise(m_Cookie);
m_oConnectionPoint = null;
m_Cookie = 0;
}
}

public void Dispose(){RemoveConnection();}
}
}

 

[Leviatano]

I don't believe you can disable the right click on the activesheet. If you set the AllowPropertyToolbox to false, it disables the Property Toolbox on the right click menu. There is no other property that can be set. The list of properties is:

ActiveCell ActivePane ActiveSheet
AllowPropertyToolbox AutoFit BuildNumber
CSVData CSVURL CanUndo
Cells Columns Constants
DataType Dirty DisplayColHeaders
DisplayGridlines DisplayHorizontalScrollBar DisplayPropertyToolbox
DisplayRowHeaders DisplayTitleBar DisplayToolbar
DisplayVerticalScrollBar EnableAutoCalculate EnableEvents
EnableUndo HTMLData HTMLURL
MajorVersion MaxHeight MaxWidth
MinorVersion MoveAfterReturn MoveAfterReturnDirection
Range RevisionNumber RightToLeft
Rows ScreenUpdating Selection
TitleBar Version ViewableRange

I can't see that there is a right click event.The list of events is:

BeforeCommand Calculate CancelEdit
Change Click Command
DblClick EndEdit KeyDown
KeyPress KeyUp MouseDown
MouseOut MouseOver MouseUp
SelectionChange SelectionChanging StartEdit
ViewChange

Like you, I think the OWC PIA is screwed up. Can you help with my post "OWC Web Component Spreadsheet: C#" in this news group?

 

[Leviatano]

Oh but you can! It is done through the Excel application events. Specifically you simply set the "Cancel" parameter to "True" inside the SheetBeforeRightClick event handler. I can do this from VBA in an XLS workbook and also from VB6 via Ole Automation.

My problem is that it does not work from C#. KB Article 830519 has something to say but it does not appear to work for Excel. Check out the post by Chris Peacock titled "Problem implementing connection point sink" in this newsgroup for a further discussion and some dodgy code by my good self!

 

[Leviatano]

Hi Snark,

There is an known issue in the Office XP PIA which will cause the problem
and the problem has been fixed in the Office 2003 PIA.
Now to workaround the problem, I think we can try to sink the problem
ourselves.

private UCOMIConnectionPoint m_oConnectionPoint;
private int m_Cookie;
private Excel.ApplicationClass exApp;


private void button1_Click(object sender, System.EventArgs e) //sink the
events
{
// QI for IConnectionPointContainer.
UCOMIConnectionPointContainer oConnPointContainer =
(UCOMIConnectionPointContainer)exApp;
// Get the GUID of the EApplication interface.
Guid guid=typeof(Excel.AppEvents).GUID;
// Find the connection point.
oConnPointContainer.FindConnectionPoint(ref guid,out m_oConnectionPoint);
// Call Advise to sink up the connection.
m_oConnectionPoint.Advise(this,out m_Cookie);
}
private void button2_Click(object sender, System.EventArgs e)
{
m_oConnectionPoint.Unadvise(m_Cookie);
System.Runtime.InteropServices.Marshal.ReleaseComObject(exApp);
GC.Collect();
}
[DispId(1560)]
public void SheetBeforeRightClick(object Sh , object Target ,ref bool
Cancel) //Event handler function
{
Cancel = true;
}
private void Form1_Load(object sender, System.EventArgs e)
{
//Create an instance of Excel .
exApp = new Excel.ApplicationClass();
// Show Excel to the user.
exApp.Visible = true;
}
How To Handle PowerPoint Events With Visual C# .NET
http://support.microsoft.com/default.aspx?scid=KB;EN-US;308825

HOW TO: Establish a COM Event Sink with Return Values in the .NET Framework
by Using Visual Basic .NET (810228)
http://support.microsoft.com/default.aspx?scid=KB;EN-US;810228

Best regards,

Peter Huang
Microsoft Online Partner Support

Get Secure! - www.microsoft.com/security
This posting is provided "AS IS" with no warranties, and confers no rights.

 

[Leviatano]

I am trying to use Excel from C# and need to disable the menu that appears when clicking the right mouse button on a cell.

I am trying to do this using the Excel.AppEvents_SheetBeforeRightClickEventHandler from my C# WinForm application.

I have a MessageBox that pops up that proves my event handler actually fires via my delegate but after setting the "Cancel" variable to "true" it has no effect for me. The Excel RMB menu appears when it should not. The Cancel parameter is declared as "ref bool".

I am wondering if there is a problem with the marshalling of this variable in the Office PIA which I am using. I would be happy to send code that demos my problem. Can someone please let me know if they can make it work ?

By the way I have already written some VB6 code that works fine and VBA code in an Excel Workbook that also works just fine as well. Both disable the menu as I require when I set "Cancel" to "True". The problem is that I need to do this from a C# application.

Can anyone shed some light on this at all ?

I am using...

Microsoft Excel 2002 (10.4302.4219) SP-2
Visual Studio 2003 v7.1.3088
Microsoft .NET Framework 1.1 v1.1.4322

I obtained the Office XP Primary Interop Assemblies from the following link

http://www.microsoft.com/downloads/...1e-3060-4f71-a6b4-01feba508e52&displaylang=en

 

[Leviatano]

Peter,

Many thanks - this works! I have put your code in a simple WinForm app and it works just fine. I am now trying to understand why the technique which I followed based on KB article 830519 does not work. I posted my code on another thread so here is a link to it

http://msdn.microsoft.com/newsgroup...724d0e27#b9ab348d-0491-44a2-a284-68f3724d0e27

Any ideas why your code works but my Q830519 styled solution does not ?

Nick

Hi Snark,

There is an known issue in the Office XP PIA which will cause the problem
and the problem has been fixed in the Office 2003 PIA.
Now to workaround the problem, I think we can try to sink the problem
ourselves.

private UCOMIConnectionPoint m_oConnectionPoint;
private int m_Cookie;
private Excel.ApplicationClass exApp;


private void button1_Click(object sender, System.EventArgs e) //sink the
events
{
// QI for IConnectionPointContainer.
UCOMIConnectionPointContainer oConnPointContainer =
(UCOMIConnectionPointContainer)exApp;
// Get the GUID of the EApplication interface.
Guid guid=typeof(Excel.AppEvents).GUID;
// Find the connection point.
oConnPointContainer.FindConnectionPoint(ref guid,out m_oConnectionPoint);
// Call Advise to sink up the connection.
m_oConnectionPoint.Advise(this,out m_Cookie);
}
private void button2_Click(object sender, System.EventArgs e)
{
m_oConnectionPoint.Unadvise(m_Cookie);
System.Runtime.InteropServices.Marshal.ReleaseComObject(exApp);
GC.Collect();
}
[DispId(1560)]
public void SheetBeforeRightClick(object Sh , object Target ,ref bool
Cancel) //Event handler function
{
Cancel = true;
}
private void Form1_Load(object sender, System.EventArgs e)
{
//Create an instance of Excel .
exApp = new Excel.ApplicationClass();
// Show Excel to the user.
exApp.Visible = true;
}
How To Handle PowerPoint Events With Visual C# .NET
http://support.microsoft.com/default.aspx?scid=KB;EN-US;308825

HOW TO: Establish a COM Event Sink with Return Values in the .NET Framework
by Using Visual Basic .NET (810228)
http://support.microsoft.com/default.aspx?scid=KB;EN-US;810228

Best regards,

Peter Huang
Microsoft Online Partner Support

Get Secure! - www.microsoft.com/security
This posting is provided "AS IS" with no warranties, and confers no rights.

 

[Leviatano]

Hi Nick,

Based on my research, we need to specified the attribute as below.
[ClassInterface(ClassInterfaceType.None)]
public class Excel10EventHelper : IExcelAppEvents10, IDisposable

So that we can guarantee that there is no default interface generate for
Excel10EventHelper class.
You may have a try and let me know the result.

Best regards,

Peter Huang
Microsoft Online Partner Support

Get Secure! - www.microsoft.com/security
This posting is provided "AS IS" with no warranties, and confers no rights.

 

[Leviatano]

Hi Nick,

Now I am researching the issue, and I will get back here and update you
with new information ASAP.

Best regards,

Peter Huang
Microsoft Online Partner Support

Get Secure! - www.microsoft.com/security
This posting is provided "AS IS" with no warranties, and confers no rights.

 

[Leviatano]

Peter,

What can I say... this solves all my problems. Vary many thanks.

Nick

Hi Nick,

Based on my research, we need to specified the attribute as below.
[ClassInterface(ClassInterfaceType.None)]
public class Excel10EventHelper : IExcelAppEvents10, IDisposable

So that we can guarantee that there is no default interface generate for
Excel10EventHelper class.
You may have a try and let me know the result.

Best regards,

Peter Huang
Microsoft Online Partner Support

Get Secure! - www.microsoft.com/security
This posting is provided "AS IS" with no warranties, and confers no rights.