C# .NET 2.0 this.Close() and ToolStripDrropD own Menus

[Eric Renken]

OK, I have a form with a menu and a tool bar. In the Menu I have a File
menu that contains a "Exit" item. When I click this Exit item. I have an
event wired to:

mnuFile.DropDow n.ItemClicked

In that event I check the:

event handler ...
if ( e.ClickedItem.T ag != null )
ProcessMenu( e.ClickedItem.T ag.ToString() )
System.Diagnost ics.Debug.Write Line( "Done" );

I do this because I have 1 function for all my menus on this screen. In
this function I have a switch statement:

switch ( tag )
{
....
case "Exit":
this.Close();
break;
....
}

This function returns up to the event handler successfully processes my
WriteLine statement, and then procedures to crash with:

{"Cannot access a disposed object.\r\nObje ct name:
'ToolStripDropD ownMenu'."}

Why am I getting this error. There is no code after this and my code in my
Dispose processes correctly also. In stepping through the code the Dispose
happens before my this.Close() returns anyway, so I know all that is
functioning correctly. My thought on what is happening here is that at this
point after the event handler is done the ToolStrip is trying to hide the
drop down control, but since my form is already disposed of the ToolStrip is
causing an error internally. I think this because I can view the drop down
menu while stepping though my code. My thought is that after I clicked that
item the drop down should have disappeared on its own. Well anyway this
feels like a bug to me in the ToolStrip control, and I think I found a work
around. In my event I added this code to the beginning:

((ToolStripDrop Down)sender).Hi de();

By doing this I know longer crash when I close my application.

Eric Renken

[Eric Renken]

Sorry about some of the bad grammar up front. Was trying to get this out
way to fast.

Eric Renken

"Eric Renken" <Er*********@ne wsgroup.nospam> wrote in message
news:Oe******** ********@TK2MSF TNGP15.phx.gbl. ..

OK, I have a form with a menu and a tool bar. In the Menu I have a File
menu that contains a "Exit" item. When I click this Exit item. I have an
event wired to:

mnuFile.DropDow n.ItemClicked

In that event I check the:

event handler ...
if ( e.ClickedItem.T ag != null )
ProcessMenu( e.ClickedItem.T ag.ToString() )
System.Diagnost ics.Debug.Write Line( "Done" );

I do this because I have 1 function for all my menus on this screen. In
this function I have a switch statement:

switch ( tag )
{
...
case "Exit":
this.Close();
break;
...
}

This function returns up to the event handler successfully processes my
WriteLine statement, and then procedures to crash with:

{"Cannot access a disposed object.\r\nObje ct name:
'ToolStripDropD ownMenu'."}

Why am I getting this error. There is no code after this and my code in
my Dispose processes correctly also. In stepping through the code the
Dispose happens before my this.Close() returns anyway, so I know all that
is functioning correctly. My thought on what is happening here is that at
this point after the event handler is done the ToolStrip is trying to hide
the drop down control, but since my form is already disposed of the
ToolStrip is causing an error internally. I think this because I can view
the drop down menu while stepping though my code. My thought is that
after I clicked that item the drop down should have disappeared on its
own. Well anyway this feels like a bug to me in the ToolStrip control,
and I think I found a work around. In my event I added this code to the
beginning:

((ToolStripDrop Down)sender).Hi de();

By doing this I know longer crash when I close my application.

Eric Renken

[Jeffrey Tan[MSFT]]

Hi Eric,

Thanks for your post.

Currently, for this issue, can you provide a little sample project to
demonstrate the problem? Then we can understand the problem context much
better. This is because the currently information you provided is not
enough for us to reproduce the problem.

Thanks

Best regards,
Jeffrey Tan
Microsoft Online Partner Support
Get Secure! - www.microsoft.com/security
This posting is provided "as is" with no warranties and confers no rights.

[Jeffrey Tan[MSFT]]

Hi Eric,

Thanks for your feedback.

Yes, with your sample project, I can reproduce out this problem.

I think you are right. If we enable first chance exception in VS2005 after
setting up the symbol correctly. We will get the following call stack
because of the ObjectDisposedE xception:
System.Windows. Forms.dll!Syste m.Windows.Forms .Control.Create Handle() Line
5581 + 0x2a bytes C#

System.Windows. Forms.dll!Syste m.Windows.Forms .ToolStripDropD own.CreateHandl e
() Line 1143 C#
System.Windows. Forms.dll!Syste m.Windows.Forms .Control.Handle .get() Line
2743 C#

System.Windows. Forms.dll!Syste m.Windows.Forms .ToolStripDropD own.ReparentToD r
opDownOwnerWind ow() Line 1657 + 0xb bytes C#

System.Windows. Forms.dll!Syste m.Windows.Forms .ToolStripDropD own.SetVisibleC o
re(bool visible = false) Line 1913 C#

System.Windows. Forms.dll!Syste m.Windows.Forms .ToolStripDropD own.OnItemClick e
d(System.Window s.Forms.ToolStr ipItemClickedEv entArgs e =
{System.Windows .Forms.ToolStri pItemClickedEve ntArgs}) Line 1358 + 0x19
bytes C#

System.Windows. Forms.dll!Syste m.Windows.Forms .ToolStrip.Hand leItemClick(Sys t
em.Windows.Form s.ToolStripItem dismissingItem = {Close}) Line 2582 C#

System.Windows. Forms.dll!Syste m.Windows.Forms .ToolStripItem. HandleClick(Sys t
em.EventArgs e = {System.EventAr gs}) Line 2769 C#

System.Windows. Forms.dll!Syste m.Windows.Forms .ToolStripItem. HandleMouseUp(S y
stem.Windows.Fo rms.MouseEventA rgs e = {X = 30 Y = 15 Button = Left}) Line
2920 C#

System.Windows. Forms.dll!Syste m.Windows.Forms .ToolStripItem. FireEventIntera c
tive(System.Eve ntArgs e, System.Windows. Forms.ToolStrip ItemEventType met)
Line 2626 C#

System.Windows. Forms.dll!Syste m.Windows.Forms .ToolStripItem. FireEvent(Syste m
.EventArgs e, System.Windows. Forms.ToolStrip ItemEventType met) Line 2607 C#

System.Windows. Forms.dll!Syste m.Windows.Forms .ToolStrip.OnMo useUp(System.Wi n
dows.Forms.Mous eEventArgs mea) Line 3531 + 0xd bytes C#

System.Windows. Forms.dll!Syste m.Windows.Forms .ToolStripDropD own.OnMouseUp(S y
stem.Windows.Fo rms.MouseEventA rgs mea = {X = 30 Y = 17 Button = Left}) Line
1439 C#
System.Windows. Forms.dll!Syste m.Windows.Forms .Control.WmMous eUp(ref
System.Windows. Forms.Message m, System.Windows. Forms.MouseButt ons button,
int clicks) Line 13032 + 0x5e bytes C#
System.Windows. Forms.dll!Syste m.Windows.Forms .Control.WndPro c(ref
System.Windows. Forms.Message m) Line 13762 C#

System.Windows. Forms.dll!Syste m.Windows.Forms .ScrollableCont rol.WndProc(ref
System.Windows. Forms.Message m) Line 1491 C#
System.Windows. Forms.dll!Syste m.Windows.Forms .ToolStrip.WndP roc(ref
System.Windows. Forms.Message m = {msg=0x202 (WM_LBUTTONUP) hwnd=0x109c0
wparam=0x0 lparam=0x11001e result=0x0}) Line 4627 C#

System.Windows. Forms.dll!Syste m.Windows.Forms .ToolStripDropD own.WndProc(ref
System.Windows. Forms.Message m) Line 2112 C#

System.Windows. Forms.dll!Syste m.Windows.Forms .Control.Contro lNativeWindow.O n
Message(ref System.Windows. Forms.Message m) Line 14049 C#

System.Windows. Forms.dll!Syste m.Windows.Forms .Control.Contro lNativeWindow.W n
dProc(ref System.Windows. Forms.Message m) Line 14104 C#

System.Windows. Forms.dll!Syste m.Windows.Forms .NativeWindow.D ebuggableCallba c
k(System.IntPtr hWnd, int msg = 514, System.IntPtr wparam, System.IntPtr
lparam) Line 777 + 0xa bytes C#
[Native to Managed Transition]
[Managed to Native Transition]

System.Windows. Forms.dll!Syste m.Windows.Forms .Application.Co mponentManager. S
ystem.Windows.F orms.UnsafeNati veMethods.IMsoC omponentManager .FPushMessageLo o
p(int dwComponentID, int reason = -1, int pvLoopData = 0) Line 2106 + 0x8
bytes C#

System.Windows. Forms.dll!Syste m.Windows.Forms .Application.Th readContext.Run M
essageLoopInner (int reason = -1, System.Windows. Forms.Applicati onContext
context = {System.Windows .Forms.Applicat ionContext}) Line 3359 + 0x1b bytes
C#

System.Windows. Forms.dll!Syste m.Windows.Forms .Application.Th readContext.Run M
essageLoop(int reason, System.Windows. Forms.Applicati onContext context)
Line 3243 + 0xa bytes C#

System.Windows. Forms.dll!Syste m.Windows.Forms .Application.Ru n(System.Window s
.Forms.Form mainForm) Line 1466 C#

MenuCrashSample .exe!MenuCrashS ample.Program.M ain() Line 17 + 0x1a bytes C#

With Reflector, we will find the following code in
System.Windows. Forms.Control.C reateHandle() method:

protected virtual void CreateHandle()
{
IntPtr ptr1 = IntPtr.Zero;
if (this.GetState( 0x800))
{
throw new ObjectDisposedE xception(base.G etType().Name);
}
.....
}

Then by using Reflector to view Control.Dispose method, we will see the
following code in finally clause:
finally
{
this.ResumeLayo ut(false);
this.SetState(0 x1000, false);
this.SetState(0 x800, true);
}

So, Control.Dispose () method turn on 0x800 flag, which causes
ObjectDisposedE xception in System.Windows. Forms.Control.C reateHandle()
method.

Currently, I think your workaround of using mnuFile.DropDow n.Hide() should
be a good one. Also, you may submit a bug request to our product team in
the link below:
http://lab.msdn.microsoft.com/produc...k/default.aspx

Thanks

Best regards,
Jeffrey Tan
Microsoft Online Partner Support
Get Secure! - www.microsoft.com/security
This posting is provided "as is" with no warranties and confers no rights.

[Eric Renken]

Jeffery,

Thanks for looking at this. I have submitted the bug to that URL you
listed. Along with the sample project.

Thanks again,

Eric Renken

""Jeffrey Tan[MSFT]"" <v-*****@online.mi crosoft.com> wrote in message
news:N7******** ******@TK2MSFTN GXA02.phx.gbl.. .

Hi Eric,

Thanks for your feedback.

Yes, with your sample project, I can reproduce out this problem.

I think you are right. If we enable first chance exception in VS2005 after
setting up the symbol correctly. We will get the following call stack
because of the ObjectDisposedE xception:
System.Windows. Forms.dll!Syste m.Windows.Forms .Control.Create Handle() Line
5581 + 0x2a bytes C#

System.Windows. Forms.dll!Syste m.Windows.Forms .ToolStripDropD own.CreateHandl e
() Line 1143 C#
System.Windows. Forms.dll!Syste m.Windows.Forms .Control.Handle .get() Line
2743 C#

System.Windows. Forms.dll!Syste m.Windows.Forms .ToolStripDropD own.ReparentToD r
opDownOwnerWind ow() Line 1657 + 0xb bytes C#

System.Windows. Forms.dll!Syste m.Windows.Forms .ToolStripDropD own.SetVisibleC o
re(bool visible = false) Line 1913 C#

System.Windows. Forms.dll!Syste m.Windows.Forms .ToolStripDropD own.OnItemClick e
d(System.Window s.Forms.ToolStr ipItemClickedEv entArgs e =
{System.Windows .Forms.ToolStri pItemClickedEve ntArgs}) Line 1358 + 0x19
bytes C#

System.Windows. Forms.dll!Syste m.Windows.Forms .ToolStrip.Hand leItemClick(Sys t
em.Windows.Form s.ToolStripItem dismissingItem = {Close}) Line 2582 C#

System.Windows. Forms.dll!Syste m.Windows.Forms .ToolStripItem. HandleClick(Sys t
em.EventArgs e = {System.EventAr gs}) Line 2769 C#

System.Windows. Forms.dll!Syste m.Windows.Forms .ToolStripItem. HandleMouseUp(S y
stem.Windows.Fo rms.MouseEventA rgs e = {X = 30 Y = 15 Button = Left}) Line
2920 C#

System.Windows. Forms.dll!Syste m.Windows.Forms .ToolStripItem. FireEventIntera c
tive(System.Eve ntArgs e, System.Windows. Forms.ToolStrip ItemEventType met)
Line 2626 C#

System.Windows. Forms.dll!Syste m.Windows.Forms .ToolStripItem. FireEvent(Syste m
EventArgs e, System.Windows. Forms.ToolStrip ItemEventType met) Line 2607 C#

System.Windows. Forms.dll!Syste m.Windows.Forms .ToolStrip.OnMo useUp(System.Wi n
dows.Forms.Mous eEventArgs mea) Line 3531 + 0xd bytes C#

System.Windows. Forms.dll!Syste m.Windows.Forms .ToolStripDropD own.OnMouseUp(S y
stem.Windows.Fo rms.MouseEventA rgs mea = {X = 30 Y = 17 Button = Left})
Line
1439 C#
System.Windows. Forms.dll!Syste m.Windows.Forms .Control.WmMous eUp(ref
System.Windows. Forms.Message m, System.Windows. Forms.MouseButt ons button,
int clicks) Line 13032 + 0x5e bytes C#
System.Windows. Forms.dll!Syste m.Windows.Forms .Control.WndPro c(ref
System.Windows. Forms.Message m) Line 13762 C#

System.Windows. Forms.dll!Syste m.Windows.Forms .ScrollableCont rol.WndProc(ref
System.Windows. Forms.Message m) Line 1491 C#
System.Windows. Forms.dll!Syste m.Windows.Forms .ToolStrip.WndP roc(ref
System.Windows. Forms.Message m = {msg=0x202 (WM_LBUTTONUP) hwnd=0x109c0
wparam=0x0 lparam=0x11001e result=0x0}) Line 4627 C#

System.Windows. Forms.dll!Syste m.Windows.Forms .ToolStripDropD own.WndProc(ref
System.Windows. Forms.Message m) Line 2112 C#

System.Windows. Forms.dll!Syste m.Windows.Forms .Control.Contro lNativeWindow.O n
Message(ref System.Windows. Forms.Message m) Line 14049 C#

System.Windows. Forms.dll!Syste m.Windows.Forms .Control.Contro lNativeWindow.W n
dProc(ref System.Windows. Forms.Message m) Line 14104 C#

System.Windows. Forms.dll!Syste m.Windows.Forms .NativeWindow.D ebuggableCallba c
k(System.IntPtr hWnd, int msg = 514, System.IntPtr wparam, System.IntPtr
lparam) Line 777 + 0xa bytes C#
[Native to Managed Transition]
[Managed to Native Transition]

System.Windows. Forms.dll!Syste m.Windows.Forms .Application.Co mponentManager. S
ystem.Windows.F orms.UnsafeNati veMethods.IMsoC omponentManager .FPushMessageLo o
p(int dwComponentID, int reason = -1, int pvLoopData = 0) Line 2106 + 0x8
bytes C#

System.Windows. Forms.dll!Syste m.Windows.Forms .Application.Th readContext.Run M
essageLoopInner (int reason = -1, System.Windows. Forms.Applicati onContext
context = {System.Windows .Forms.Applicat ionContext}) Line 3359 + 0x1b
bytes
C#

System.Windows. Forms.dll!Syste m.Windows.Forms .Application.Th readContext.Run M
essageLoop(int reason, System.Windows. Forms.Applicati onContext context)
Line 3243 + 0xa bytes C#

System.Windows. Forms.dll!Syste m.Windows.Forms .Application.Ru n(System.Window s
Forms.Form mainForm) Line 1466 C#

MenuCrashSample .exe!MenuCrashS ample.Program.M ain() Line 17 + 0x1a bytes
C#

With Reflector, we will find the following code in
System.Windows. Forms.Control.C reateHandle() method:

protected virtual void CreateHandle()
{
IntPtr ptr1 = IntPtr.Zero;
if (this.GetState( 0x800))
{
throw new ObjectDisposedE xception(base.G etType().Name);
}
....
}

Then by using Reflector to view Control.Dispose method, we will see the
following code in finally clause:
finally
{
this.ResumeLayo ut(false);
this.SetState(0 x1000, false);
this.SetState(0 x800, true);
}

So, Control.Dispose () method turn on 0x800 flag, which causes
ObjectDisposedE xception in System.Windows. Forms.Control.C reateHandle()
method.

Currently, I think your workaround of using mnuFile.DropDow n.Hide() should
be a good one. Also, you may submit a bug request to our product team in
the link below:
http://lab.msdn.microsoft.com/produc...k/default.aspx

Thanks

Best regards,
Jeffrey Tan
Microsoft Online Partner Support
Get Secure! - www.microsoft.com/security
This posting is provided "as is" with no warranties and confers no rights.

[Jeffrey Tan[MSFT]]

Ok. If you need further help, please feel free to post. Thanks

Best regards,
Jeffrey Tan
Microsoft Online Partner Support
Get Secure! - www.microsoft.com/security
This posting is provided "as is" with no warranties and confers no rights.