excel process not terminating properly

[chuckie_9497@hotmail.com]

hello all you gurus. I am struggling with releasing com objects. I
have isolated the problem to the code below. Objects are released and
the process ends until I
use "int k = sheet.Count;" Then the process does not end. So I feel
confident the problem occurrs here. It appears another reference is
created that needs to be closed. Can anyone tell me how to do
this? :)
Thank you

Excel.Workbook workbook =
(Excel.Workbook )excelapplicati on.ActiveWorkbo ok;
Excel.Sheets sheet = workbook.Worksh eets;

// problem here
int k = sheet.Count;

System.Runtime. InteropServices .Marshal.Releas eComObject(shee t);
sheet = null;
System.Runtime. InteropServices .Marshal.Releas eComObject(work book);
workbook = null;

[Scott M.]

Re: excel process not terminating properly

Try adding the following just BEFORE your call ReleaseCOMObjec t on them:

sheet = null;
workbook = null;



<chuckie_9497@h otmail.comwrote in message
news:1176917315 .668226.159170@ y80g2000hsf.goo glegroups.com.. .

hello all you gurus. I am struggling with releasing com objects. I
have isolated the problem to the code below. Objects are released and
the process ends until I
use "int k = sheet.Count;" Then the process does not end. So I feel
confident the problem occurrs here. It appears another reference is
created that needs to be closed. Can anyone tell me how to do
this? :)
Thank you
>
Excel.Workbook workbook =
(Excel.Workbook )excelapplicati on.ActiveWorkbo ok;
Excel.Sheets sheet = workbook.Worksh eets;
>
// problem here
int k = sheet.Count;
>
System.Runtime. InteropServices .Marshal.Releas eComObject(shee t);
sheet = null;
System.Runtime. InteropServices .Marshal.Releas eComObject(work book);
workbook = null;
>

[Herfried K. Wagner [MVP]]

Re: excel process not terminating properly

"Scott M." <s-mar@nospam.nosp amschrieb:

Try adding the following just BEFORE your call ReleaseCOMObjec t on them:
>
sheet = null;
workbook = null;

Bad idea, because 'ReleaseComObje ct' won't release the objects if a null
reference is passed to it.

--
M S Herfried K. Wagner
M V P <URL:http://dotnet.mvps.org/>
V B <URL:http://dotnet.mvps.org/dotnet/faqs/>

[Herfried K. Wagner [MVP]]

Re: excel process not terminating properly

<chuckie_9497@h otmail.comschri eb:

I am struggling with releasing com objects. I
have isolated the problem to the code below. Objects are released and
the process ends until I
use "int k = sheet.Count;" Then the process does not end.

PRB: Office Application Does Not Quit After Automation from Visual Studio
..NET Client
<URL:http://support.microso ft.com/?scid=kb;EN-US;317109>
-"Troubleshootin g"

--
M S Herfried K. Wagner
M V P <URL:http://dotnet.mvps.org/>
V B <URL:http://dotnet.mvps.org/dotnet/faqs/>

[Scott M.]

Re: excel process not terminating properly

Your link shows (in a more elaborate way) how to do what the OP is already
doing (RleaseCOMObjec t and set to null). Is there a particular part of the
article that you suggest?


"Herfried K. Wagner [MVP]" <hirf-spam-me-here@gmx.atwrot e in message
news:uFncFgfgHH A.4284@TK2MSFTN GP06.phx.gbl...

<chuckie_9497@h otmail.comschri eb:

>I am struggling with releasing com objects. I
>have isolated the problem to the code below. Objects are released and
>the process ends until I
>use "int k = sheet.Count;" Then the process does not end.

>
PRB: Office Application Does Not Quit After Automation from Visual Studio
.NET Client
<URL:http://support.microso ft.com/?scid=kb;EN-US;317109>
-"Troubleshootin g"
>
--
M S Herfried K. Wagner
M V P <URL:http://dotnet.mvps.org/>
V B <URL:http://dotnet.mvps.org/dotnet/faqs/>

[Herfried K. Wagner [MVP]]

Re: excel process not terminating properly

"Scott M." <s-mar@nospam.nosp amschrieb:

Your link shows (in a more elaborate way) how to do what the OP is already
doing (RleaseCOMObjec t and set to null). Is there a particular part of
the article that you suggest?

I suggest the "more elaborate way".

--
M S Herfried K. Wagner
M V P <URL:http://dotnet.mvps.org/>
V B <URL:http://dotnet.mvps.org/dotnet/faqs/>

[chuckie_9497@hotmail.com]

Re: excel process not terminating properly

On Apr 18, 3:48 pm, "Herfried K. Wagner [MVP]" <hirf-spam-me-
h...@gmx.atwrot e:

<chuckie_9...@h otmail.comschri eb:
>

I am struggling with releasing com objects. I
have isolated the problem to the code below. Objects are released and
the process ends until I
use "int k = sheet.Count;" Then the process does not end.

>
PRB: Office Application Does Not Quit After Automation from Visual Studio
.NET Client
<URL:http://support.microso ft.com/?scid=kb;EN-US;317109>
-"Troubleshootin g"
>
--
M S Herfried K. Wagner
M V P <URL:http://dotnet.mvps.org/>
V B <URL:http://dotnet.mvps.org/dotnet/faqs/>

thank you for your resposnse and I have to admit I am somewhat
confused (I guess that's obvious). I read the article and maybe I
missed the obvious, but I do use GC.Collect() and
GC.WaitForPendi ngFinalizers() and excelapplicatio n.quit(). And I
think I understand that I must explicitly reference any object that is
implicitly created. So, I think (I am probably wrong) int k =
sheet.Count; creates an implicit reference that I must explicitly
reference so I can remove the reference. Is this correct? If so , how
do I do that? If I am wrong, please correct me. Everything works
fine until this statement is added. Thank you

[chuckie_9497@hotmail.com]

Re: excel process not terminating properly

On Apr 18, 3:48 pm, "Herfried K. Wagner [MVP]" <hirf-spam-me-
h...@gmx.atwrot e:

<chuckie_9...@h otmail.comschri eb:
>

I am struggling with releasing com objects. I
have isolated the problem to the code below. Objects are released and
the process ends until I
use "int k = sheet.Count;" Then the process does not end.

>
PRB: Office Application Does Not Quit After Automation from Visual Studio
.NET Client
<URL:http://support.microso ft.com/?scid=kb;EN-US;317109>
-"Troubleshootin g"
>
--
M S Herfried K. Wagner
M V P <URL:http://dotnet.mvps.org/>
V B <URL:http://dotnet.mvps.org/dotnet/faqs/>

thank you for your resposnse and I have to admit I am somewhat
confused (I guess that's obvious). I read the article and maybe I
missed the obvious, but I do use GC.Collect() and
GC.WaitForPendi ngFinalizers() and excelapplicatio n.quit(). And I
think I understand that I must explicitly reference any object that is
implicitly created. So, I think (I am probably wrong) int k =
sheet.Count; creates an implicit reference that I must explicitly
reference so I can remove the reference. Is this correct? If so , how
do I do that? If I am wrong, please correct me. Everything works
fine until this statement is added. Thank you

[Willy Denoyette [MVP]]

Re: excel process not terminating properly

<chuckie_9497@h otmail.comwrote in message
news:1176929507 .407777.288290@ b58g2000hsg.goo glegroups.com.. .

On Apr 18, 3:48 pm, "Herfried K. Wagner [MVP]" <hirf-spam-me-
h...@gmx.atwrot e:

><chuckie_9...@ hotmail.comschr ieb:
>>

I am struggling with releasing com objects. I
have isolated the problem to the code below. Objects are released and
the process ends until I
use "int k = sheet.Count;" Then the process does not end.

>>
>PRB: Office Application Does Not Quit After Automation from Visual Studio
>.NET Client
><URL:http://support.microso ft.com/?scid=kb;EN-US;317109>
>-"Troubleshootin g"
>>
>--
> M S Herfried K. Wagner
>M V P <URL:http://dotnet.mvps.org/>
> V B <URL:http://dotnet.mvps.org/dotnet/faqs/>

>
thank you for your resposnse and I have to admit I am somewhat
confused (I guess that's obvious). I read the article and maybe I
missed the obvious, but I do use GC.Collect() and
GC.WaitForPendi ngFinalizers() and excelapplicatio n.quit(). And I
think I understand that I must explicitly reference any object that is
implicitly created. So, I think (I am probably wrong) int k =
sheet.Count; creates an implicit reference that I must explicitly
reference so I can remove the reference. Is this correct? If so , how
do I do that? If I am wrong, please correct me. Everything works
fine until this statement is added. Thank you
>

No, Count does not create an reference to a COM object, sheet holds a reference to the COM
interface.
But as long as you don't post a *complete* sample, that illustrates the issue, you won't get
any sensible answers.

A complete sample looks something like this:

using System;
using System.Collecti ons.Generic;
using System.Text;
using System.Globaliz ation;
using System.Reflecti on;

using Exl = Microsoft.Offic e.Interop.Excel ;
namespace OffExc
{
class Program
{
[STAThread]
static void Main(string[] args)
{
System.Threadin g.Thread.Curren tThread.Current Culture = new CultureInfo( "en-US",
false );
Exl.Application exApp = new Microsoft.Offic e.Interop.Excel .ApplicationCla ss();
// Reference 1
Exl.Workbook wb = exApp.Workbooks .Add(Missing.Va lue); // Reference 2
exApp.Visible = true;
// Keep Excel visible for a while..
System.Threadin g.Thread.Sleep( 3000);
Exl.Sheets sheet = wb.Worksheets; // // Reference 3
int k = sheet.Count;
// Quit
exApp.Quit();
// Release the three COM references...
System.Runtime. InteropServices .Marshal.Releas eComObject(shee t);
System.Runtime. InteropServices .Marshal.Releas eComObject(wb);
System.Runtime. InteropServices .Marshal.Releas eComObject(exAp p);
GC.Collect();
// Let the finalizer run, this one will delete the unmanaged COM wrappers,
// if for one or another reason, the finalizer cannot run to completion,
// chances are that the Excel process won't get removed !!!!!!!!
GC.WaitForPendi ngFinalizers();
// Excel should be gone by now... keep the console processrunning for a while
System.Threadin g.Thread.Sleep( 30000);
}
}
}

And above code works as expected on my box.

Willy.

[PFC Sadr]

Re: excel process not terminating properly

this is a scam

the problem is using DAO. screw DAO and you won't have this problem

ADO works like a charm






On Apr 18, 12:48 pm, "Herfried K. Wagner [MVP]" <hirf-spam-me-
h...@gmx.atwrot e:

<chuckie_9...@h otmail.comschri eb:
>

I am struggling with releasing com objects. I
have isolated the problem to the code below. Objects are released and
the process ends until I
use "int k = sheet.Count;" Then the process does not end.

>
PRB: Office Application Does Not Quit After Automation from Visual Studio
.NET Client
<URL:http://support.microso ft.com/?scid=kb;EN-US;317109>
-"Troubleshootin g"
>
--
M S Herfried K. Wagner
M V P <URL:http://dotnet.mvps.org/>
V B <URL:http://dotnet.mvps.org/dotnet/faqs/>

[chuckie_9497@hotmail.com]

Re: excel process not terminating properly

On Apr 18, 5:38 pm, "Willy Denoyette [MVP]"
<willy.denoye.. .@telenet.bewro te:

<chuckie_9...@h otmail.comwrote in message
>
news:1176929507 .407777.288290@ b58g2000hsg.goo glegroups.com.. .
>
>
>
>
>

On Apr 18, 3:48 pm, "Herfried K. Wagner [MVP]" <hirf-spam-me-
h...@gmx.atwrot e:

<chuckie_9...@h otmail.comschri eb:

>

I am struggling with releasing com objects. I
have isolated the problem to the code below. Objects are released and
the process ends until I
use "int k = sheet.Count;" Then the process does not end.

>

PRB: Office Application Does Not Quit After Automation from Visual Studio
.NET Client
<URL:http://support.microso ft.com/?scid=kb;EN-US;317109>
-"Troubleshootin g"

>

--
M S Herfried K. Wagner
M V P <URL:http://dotnet.mvps.org/>
V B <URL:http://dotnet.mvps.org/dotnet/faqs/>

>

thank you for your resposnse and I have to admit I am somewhat
confused (I guess that's obvious). I read the article and maybe I
missed the obvious, but I do use GC.Collect() and
GC.WaitForPendi ngFinalizers() and excelapplicatio n.quit(). And I
think I understand that I must explicitly reference any object that is
implicitly created. So, I think (I am probably wrong) int k =
sheet.Count; creates an implicit reference that I must explicitly
reference so I can remove the reference. Is this correct? If so , how
do I do that? If I am wrong, please correct me. Everything works
fine until this statement is added. Thank you

>
No, Count does not create an reference to a COM object, sheet holds a reference to the COM
interface.
But as long as you don't post a *complete* sample, that illustrates the issue, you won't get
any sensible answers.
>
A complete sample looks something like this:
>
using System;
using System.Collecti ons.Generic;
using System.Text;
using System.Globaliz ation;
using System.Reflecti on;
>
using Exl = Microsoft.Offic e.Interop.Excel ;
namespace OffExc
{
class Program
{
[STAThread]
static void Main(string[] args)
{
System.Threadin g.Thread.Curren tThread.Current Culture = new CultureInfo( "en-US",
false );
Exl.Application exApp = new Microsoft.Offic e.Interop.Excel .ApplicationCla ss();
// Reference 1
Exl.Workbook wb = exApp.Workbooks .Add(Missing.Va lue); // Reference 2
exApp.Visible = true;
// Keep Excel visible for a while..
System.Threadin g.Thread.Sleep( 3000);
Exl.Sheets sheet = wb.Worksheets; // // Reference 3
int k = sheet.Count;
// Quit
exApp.Quit();
// Release the three COM references...
System.Runtime. InteropServices .Marshal.Releas eComObject(shee t);
System.Runtime. InteropServices .Marshal.Releas eComObject(wb);
System.Runtime. InteropServices .Marshal.Releas eComObject(exAp p);
GC.Collect();
// Let the finalizer run, this one will delete the unmanaged COM wrappers,
// if for one or another reason, the finalizer cannot run to completion,
// chances are that the Excel process won't get removed !!!!!!!!
GC.WaitForPendi ngFinalizers();
// Excel should be gone by now... keep the console processrunning for a while
System.Threadin g.Thread.Sleep( 30000);
}
}
>
}
>
And above code works as expected on my box.
>
Willy.- Hide quoted text -
>
- Show quoted text -

thank you gentlmen for your help. the following seems to be working
correctly. of course I have alot more to do but this will get me
started. Is there a "better" way to save the workbook (ie, use
wb.saveas) and is there a better way way to enumerate and delete
unwanted sheets? Also, I realize error checking needs to be
implemented. Thanks again for your assistance.

using System;
using System.Reflecti on;
using System.Threadin g;
using System.Globaliz ation;
using Exl = Microsoft.Offic e.Interop.Excel ;

namespace mynamespace
{
class myexcel
{
public void test()
{
System.Threadin g.Thread.Curren tThread.Current Culture = new
CultureInfo("en-US", false);
Exl.Application exApp = new
Microsoft.Offic e.Interop.Excel .ApplicationCla ss();
// Reference 1
Exl.Workbook wb = exApp.Workbooks .Add(Missing.Va lue); //
Reference 2
exApp.Visible = true;
Exl.Sheets sheet = wb.Worksheets; // Reference 3
// set active sheet
Exl.Worksheet activesheet = (Exl.Worksheet) wb.ActiveSheet;
activesheet.Nam e = "testsheet" ;
// write to cell A1
Exl.Range range;
range = activesheet.get _Range("A1", Missing.Value);
range.Value2 = "test input";

System.Runtime. InteropServices .Marshal.Releas eComObject(rang e);
// disable alerts so I'm not prompted when a worksheet is
deleted
exApp.DisplayAl erts = false;
// delete a sheet
for (int i = 1; i <= sheet.Count; i++)
{
// would like to delete
Exl.Worksheet ob = (Exl.Worksheet) exApp.Worksheet s[i];
if (ob.Name.ToLowe r().Substring(0 , 5).Equals("shee t"))
ob.Delete();
ReleaseComObjec t(ob);
ob = null;
}
// save the workbook
exApp.ActiveWor kbook.Close(tru e, @"c:\testxls.xl s",
Missing.Value);
// Quit
exApp.Quit();
// Release the COM references...
ReleaseComObjec t(activesheet);
ReleaseComObjec t(sheet);
ReleaseComObjec t(wb);
ReleaseComObjec t(exApp);
GC.Collect();
// Let the finalizer run, this one will delete the unmanaged
COM wrappers,
// if for one or another reason, the finalizer cannot run to
completion,
// chances are that the Excel process won't get
removed !!!!!!!!
GC.WaitForPendi ngFinalizers();
// Excel should be gone by now... keep the console
processrunning for a while
System.Threadin g.Thread.Sleep( 3000);
}
public void ReleaseComObjec t(Object reference)
{
try
{
while
(System.Runtime .InteropService s.Marshal.Relea seComObject(ref erence) >
-1) ;
}
catch (Exception ex)
{
// handle exception
}
finally
{
reference = null;
}
}
}
}

[Scott M.]

Re: excel process not terminating properly

By more elaborate, I just meant that they've broken the release of the
object into a separate function. It seems that the OP is doing the same
thing in his code, just not in a separate function. What, exactly, is the
article showing that the OP isn't doing?


"Herfried K. Wagner [MVP]" <hirf-spam-me-here@gmx.atwrot e in message
news:ON9olnfgHH A.2640@TK2MSFTN GP06.phx.gbl...

"Scott M." <s-mar@nospam.nosp amschrieb:

>Your link shows (in a more elaborate way) how to do what the OP is
>already doing (RleaseCOMObjec t and set to null). Is there a particular
>part of the article that you suggest?

>
I suggest the "more elaborate way".
>
--
M S Herfried K. Wagner
M V P <URL:http://dotnet.mvps.org/>
V B <URL:http://dotnet.mvps.org/dotnet/faqs/>

[Herfried K. Wagner [MVP]]

Re: excel process not terminating properly

"Scott M." <s-mar@nospam.nosp amschrieb:

By more elaborate, I just meant that they've broken the release of the
object into a separate function. It seems that the OP is doing the same
thing in his code, just not in a separate function. What, exactly, is the
article showing that the OP isn't doing?

Take a look at the information in the "Troubleshootin g" section of the
document.

--
M S Herfried K. Wagner
M V P <URL:http://dotnet.mvps.org/>
V B <URL:http://dotnet.mvps.org/dotnet/faqs/>

[Willy Denoyette [MVP]]

Re: excel process not terminating properly

<chuckie_9497@h otmail.comwrote in message
news:1176943062 .446393.154740@ q75g2000hsh.goo glegroups.com.. .

On Apr 18, 5:38 pm, "Willy Denoyette [MVP]"
<willy.denoye.. .@telenet.bewro te:

><chuckie_9...@ hotmail.comwrot e in message
>>
>news:117692950 7.407777.288290 @b58g2000hsg.go oglegroups.com. ..
>>
>>
>>
>>
>>

On Apr 18, 3:48 pm, "Herfried K. Wagner [MVP]" <hirf-spam-me-
h...@gmx.atwrot e:
><chuckie_9...@ hotmail.comschr ieb:

>>

I am struggling with releasing com objects. I
have isolated the problem to the code below. Objects are released and
the process ends until I
use "int k = sheet.Count;" Then the process does not end.

>>

>PRB: Office Application Does Not Quit After Automation from Visual Studio
>.NET Client
><URL:http://support.microso ft.com/?scid=kb;EN-US;317109>
>-"Troubleshootin g"

>>

>--
> M S Herfried K. Wagner
>M V P <URL:http://dotnet.mvps.org/>
> V B <URL:http://dotnet.mvps.org/dotnet/faqs/>

>>

thank you for your resposnse and I have to admit I am somewhat
confused (I guess that's obvious). I read the article and maybe I
missed the obvious, but I do use GC.Collect() and
GC.WaitForPendi ngFinalizers() and excelapplicatio n.quit(). And I
think I understand that I must explicitly reference any object that is
implicitly created. So, I think (I am probably wrong) int k =
sheet.Count; creates an implicit reference that I must explicitly
reference so I can remove the reference. Is this correct? If so , how
do I do that? If I am wrong, please correct me. Everything works
fine until this statement is added. Thank you

>>
>No, Count does not create an reference to a COM object, sheet holds a reference to the
>COM
>interface.
>But as long as you don't post a *complete* sample, that illustrates the issue, you won't
>get
>any sensible answers.
>>
>A complete sample looks something like this:
>>
>using System;
>using System.Collecti ons.Generic;
>using System.Text;
>using System.Globaliz ation;
>using System.Reflecti on;
>>
>using Exl = Microsoft.Offic e.Interop.Excel ;
>namespace OffExc
>{
> class Program
> {
> [STAThread]
> static void Main(string[] args)
> {
> System.Threadin g.Thread.Curren tThread.Current Culture = new CultureInfo(
>"en-US",
>false );
> Exl.Application exApp = new
>Microsoft.Offi ce.Interop.Exce l.ApplicationCl ass();
>// Reference 1
> Exl.Workbook wb = exApp.Workbooks .Add(Missing.Va lue); // Reference 2
> exApp.Visible = true;
> // Keep Excel visible for a while..
> System.Threadin g.Thread.Sleep( 3000);
> Exl.Sheets sheet = wb.Worksheets; // // Reference 3
> int k = sheet.Count;
> // Quit
> exApp.Quit();
> // Release the three COM references...
> System.Runtime. InteropServices .Marshal.Releas eComObject(shee t);
> System.Runtime. InteropServices .Marshal.Releas eComObject(wb);
> System.Runtime. InteropServices .Marshal.Releas eComObject(exAp p);
> GC.Collect();
> // Let the finalizer run, this one will delete the unmanaged COM wrappers,
> // if for one or another reason, the finalizer cannot run to completion,
> // chances are that the Excel process won't get removed !!!!!!!!
> GC.WaitForPendi ngFinalizers();
> // Excel should be gone by now... keep the console processrunning for a while
> System.Threadin g.Thread.Sleep( 30000);
> }
> }
>>
>}
>>
>And above code works as expected on my box.
>>
>Willy.- Hide quoted text -
>>
>- Show quoted text -

>
thank you gentlmen for your help. the following seems to be working
correctly. of course I have alot more to do but this will get me
started. Is there a "better" way to save the workbook (ie, use
wb.saveas) and is there a better way way to enumerate and delete
unwanted sheets? Also, I realize error checking needs to be
implemented. Thanks again for your assistance.
>
using System;
using System.Reflecti on;
using System.Threadin g;
using System.Globaliz ation;
using Exl = Microsoft.Offic e.Interop.Excel ;
>
namespace mynamespace
{
class myexcel
{
public void test()
{
System.Threadin g.Thread.Curren tThread.Current Culture = new
CultureInfo("en-US", false);
Exl.Application exApp = new
Microsoft.Offic e.Interop.Excel .ApplicationCla ss();
// Reference 1
Exl.Workbook wb = exApp.Workbooks .Add(Missing.Va lue); //
Reference 2
exApp.Visible = true;
Exl.Sheets sheet = wb.Worksheets; // Reference 3
// set active sheet
Exl.Worksheet activesheet = (Exl.Worksheet) wb.ActiveSheet;
activesheet.Nam e = "testsheet" ;
// write to cell A1
Exl.Range range;
range = activesheet.get _Range("A1", Missing.Value);
range.Value2 = "test input";
>
System.Runtime. InteropServices .Marshal.Releas eComObject(rang e);
// disable alerts so I'm not prompted when a worksheet is
deleted
exApp.DisplayAl erts = false;
// delete a sheet
for (int i = 1; i <= sheet.Count; i++)
{
// would like to delete
Exl.Worksheet ob = (Exl.Worksheet) exApp.Worksheet s[i];
if (ob.Name.ToLowe r().Substring(0 , 5).Equals("shee t"))
ob.Delete();
ReleaseComObjec t(ob);
ob = null;
}
// save the workbook
exApp.ActiveWor kbook.Close(tru e, @"c:\testxls.xl s",
Missing.Value);
// Quit
exApp.Quit();
// Release the COM references...
ReleaseComObjec t(activesheet);
ReleaseComObjec t(sheet);
ReleaseComObjec t(wb);
ReleaseComObjec t(exApp);
GC.Collect();
// Let the finalizer run, this one will delete the unmanaged
COM wrappers,
// if for one or another reason, the finalizer cannot run to
completion,
// chances are that the Excel process won't get
removed !!!!!!!!
GC.WaitForPendi ngFinalizers();
// Excel should be gone by now... keep the console
processrunning for a while
System.Threadin g.Thread.Sleep( 3000);
}
public void ReleaseComObjec t(Object reference)
{
try
{
while
(System.Runtime .InteropService s.Marshal.Relea seComObject(ref erence) >
-1) ;
}
catch (Exception ex)
{
// handle exception
}
finally
{
reference = null;
}
}
}
}
>
>
>
>

No need to make it that complicated, each sheet will share the same COM object reference,
that means that you only have to release it once when done.

// delete default sheets
Exl.Worksheet ob = null;
for (int i = 1; i <= sheet.Count; i++)
{
// would like to delete
ob = (Exl.Worksheet) exApp.Worksheet s[i];
if(ob.Name.Star tsWith("Sheet") ) ob.Delete();
}
// release the single Worksheet COM interface used by ob ...
System.Runtime. InteropServices .Marshal.Releas eComObject(ob);
// create new sheet...


No need for the ReleaseComObjec t method either.

Willy.