Hi,

I have an handle on a bitmap (FromHBitmap by Alex Yakhnin).
I'd like to close this handle with CloseHandle Method in core.dll but it
seems to me that method has no effect.

I use DeleteObject but it seems to me there are small memory leaks...

How can I do ?

Thanks

Best Regards

Which handle are you trying to de-allocate?

Could you show your code?
--
Alex Yakhnin, .NET CF MVP
www.intelliprog.com | www.opennetcf.org


"Freddyboy" wrote:

> Hi,
>
> I have an handle on a bitmap (FromHBitmap by Alex Yakhnin).
> I'd like to close this handle with CloseHandle Method in core.dll but it
> seems to me that method has no effect.
>
> I use DeleteObject but it seems to me there are small memory leaks...
>
> How can I do ?
>
> Thanks
>
> Best Regards

The DeleteObject should work for you to delete bitmap (HBITMAP). How did
you know that you have "small memory leaks"?

--
Sergey Bogdanov
http://www.sergeybogdanov.com


Freddyboy wrote:
> Hi,
>
> I have an handle on a bitmap (FromHBitmap by Alex Yakhnin).
> I'd like to close this handle with CloseHandle Method in core.dll but it
> seems to me that method has no effect.
>
> I use DeleteObject but it seems to me there are small memory leaks...
>
> How can I do ?
>
> Thanks
>
> Best Regards

Hi Alex, Hi Sergey

yes I can show my code of course.

[DllImport("coredll.dll", SetLastError=true)]
public static extern bool CloseHandle(IntPtr hObject);
....
// get an handle to a bitmap
IntPtr hBitmap;
hBitmap = NDCaptureUtility.CreateGreyImageInDeviceContext(myHdc);
.....
// create bitmap with an handle
myBmp = BitmapBuffer.FromHbitmap(hBitmap);
....
// delete handle (unmanaged ressource) with close handle
CloseHandle(hBitmap); // the value which is return is false

// That's why I used DeleteObject
DeleteObject(hBitmap);

But when I analyse Memory with Majerus's tools (www.phm.lu), I can see the
memory is more and more used.

I think my problem is hBitmap.

CreateGreyImageInDeviceContext is a method which is in a C Dll. There are
some methods which send some messages and with methods I can perform a
preview and I can take some pictures. Maybe a problem with unmaneged Window
Message ? I know also compact framework service pack 3 which correct some
bugs with the marshalling between C# and C

What do you think about this ?

Thanks

Best Regards.

Fred



"Alex Yakhnin [MVP]" wrote:

> Which handle are you trying to de-allocate?
>
> Could you show your code?
> --
> Alex Yakhnin, .NET CF MVP
> www.intelliprog.com | www.opennetcf.org
>
>
> "Freddyboy" wrote:
>
> > Hi,
> >
> > I have an handle on a bitmap (FromHBitmap by Alex Yakhnin).
> > I'd like to close this handle with CloseHandle Method in core.dll but it
> > seems to me that method has no effect.
> >
> > I use DeleteObject but it seems to me there are small memory leaks...
> >
> > How can I do ?
> >
> > Thanks
> >
> > Best Regards

Hi Sergey,

I used Majerus's tools (www.phm.lu) to analyse Memory. When my application
is running I can see memory is more and more used.

Thanks

"Sergey Bogdanov" wrote:

> The DeleteObject should work for you to delete bitmap (HBITMAP). How did
> you know that you have "small memory leaks"?
>
> --
> Sergey Bogdanov
> http://www.sergeybogdanov.com
>
>
> Freddyboy wrote:
> > Hi,
> >
> > I have an handle on a bitmap (FromHBitmap by Alex Yakhnin).
> > I'd like to close this handle with CloseHandle Method in core.dll but it
> > seems to me that method has no effect.
> >
> > I use DeleteObject but it seems to me there are small memory leaks...
> >
> > How can I do ?
> >
> > Thanks
> >
> > Best Regards
>

I believe, the problem indeed that you do not free myHdc handle?

--
Sergey Bogdanov
http://www.sergeybogdanov.com


Freddyboy wrote:
> Hi Alex, Hi Sergey
>
> yes I can show my code of course.
>
> [DllImport("coredll.dll", SetLastError=true)]
> public static extern bool CloseHandle(IntPtr hObject);
> ...
> // get an handle to a bitmap
> IntPtr hBitmap;
> hBitmap = NDCaptureUtility.CreateGreyImageInDeviceContext(myHdc);
> ....
> // create bitmap with an handle
> myBmp = BitmapBuffer.FromHbitmap(hBitmap);
> ...
> // delete handle (unmanaged ressource) with close handle
> CloseHandle(hBitmap); // the value which is return is false
>
> // That's why I used DeleteObject
> DeleteObject(hBitmap);
>
> But when I analyse Memory with Majerus's tools (www.phm.lu), I can see the
> memory is more and more used.
>
> I think my problem is hBitmap.
>
> CreateGreyImageInDeviceContext is a method which is in a C Dll. There are
> some methods which send some messages and with methods I can perform a
> preview and I can take some pictures. Maybe a problem with unmaneged Window
> Message ? I know also compact framework service pack 3 which correct some
> bugs with the marshalling between C# and C
>
> What do you think about this ?
>
> Thanks
>
> Best Regards.
>
> Fred
>
>
>
> "Alex Yakhnin [MVP]" wrote:
>
>
>>Which handle are you trying to de-allocate?
>>
>>Could you show your code?
>>--
>>Alex Yakhnin, .NET CF MVP
>>www.intelliprog.com | www.opennetcf.org
>>
>>
>>"Freddyboy" wrote:
>>
>>
>>>Hi,
>>>
>>>I have an handle on a bitmap (FromHBitmap by Alex Yakhnin).
>>>I'd like to close this handle with CloseHandle Method in core.dll but it
>>>seems to me that method has no effect.
>>>
>>>I use DeleteObject but it seems to me there are small memory leaks...
>>>
>>>How can I do ?
>>>
>>>Thanks
>>>
>>>Best Regards

Are you ever disposing myBmp? Are you ever actually running out of memory?

-Chris



"Freddyboy" <(E-Mail Removed)> wrote in message
news:F49DDCAF-5BAC-4237-95A3-(E-Mail Removed)...
> Hi Alex, Hi Sergey
>
> yes I can show my code of course.
>
> [DllImport("coredll.dll", SetLastError=true)]
> public static extern bool CloseHandle(IntPtr hObject);
> ...
> // get an handle to a bitmap
> IntPtr hBitmap;
> hBitmap = NDCaptureUtility.CreateGreyImageInDeviceContext(myHdc);
> ....
> // create bitmap with an handle
> myBmp = BitmapBuffer.FromHbitmap(hBitmap);
> ...
> // delete handle (unmanaged ressource) with close handle
> CloseHandle(hBitmap); // the value which is return is false
>
> // That's why I used DeleteObject
> DeleteObject(hBitmap);
>
> But when I analyse Memory with Majerus's tools (www.phm.lu), I can see the
> memory is more and more used.
>
> I think my problem is hBitmap.
>
> CreateGreyImageInDeviceContext is a method which is in a C Dll. There are
> some methods which send some messages and with methods I can perform a
> preview and I can take some pictures. Maybe a problem with unmaneged
> Window
> Message ? I know also compact framework service pack 3 which correct some
> bugs with the marshalling between C# and C
>
> What do you think about this ?
>
> Thanks
>
> Best Regards.
>
> Fred
>
>
>
> "Alex Yakhnin [MVP]" wrote:
>
>> Which handle are you trying to de-allocate?
>>
>> Could you show your code?
>> --
>> Alex Yakhnin, .NET CF MVP
>> www.intelliprog.com | www.opennetcf.org
>>
>>
>> "Freddyboy" wrote:
>>
>> > Hi,
>> >
>> > I have an handle on a bitmap (FromHBitmap by Alex Yakhnin).
>> > I'd like to close this handle with CloseHandle Method in core.dll but
>> > it
>> > seems to me that method has no effect.
>> >
>> > I use DeleteObject but it seems to me there are small memory leaks...
>> >
>> > How can I do ?
>> >
>> > Thanks
>> >
>> > Best Regards

I perform a dispose on myBmp and I dispose also myHdc.
Complete Code:
// Constructor
public NDImager()
{
// Get form handle
myHandle = GetActiveWindow();
if (myHandle != IntPtr.Zero)
{
// get handle device context
myHdc = OpenNETCF.Win32.Core.GetDC(myHandle);
// build a NDImagerMessageWindow object
myMsgWnd = new NDImagerMessageWindow(this);
}
}

// An other Method which used myBmp, myHdc ...
// this code is in a switch
// I think it's here there is a problem with memory

// get an handle to a bitmap
IntPtr hBitmap;
hBitmap = NDCaptureUtility.CreateGreyImageInDeviceContext(myHdc);

// delete last bitmap
if (myBmp != null)
{
myBmp.Dispose();
myBmp = null;
}

// if handle is not null
if (hBitmap != IntPtr.Zero)
{
// create bitmap with an handle
myBmp = NDBitmapBuffer.FromHbitmap(hBitmap);
// display bitmap
myPictureBox.Image = myBmp;
myPictureBox.Invalidate();

// delete handle (unmanaged ressource)
// the value which is returned by closehandle is false that's why I use
DeleteObject
DeleteObject(hBitmap);
}
protected void Dispose(bool disposing)
{
if (disposing)
{
// Stop Window Message
StopRunningWithMessageWnd();
Thread.Sleep(500);

// Remember to release the device context
OpenNETCF.Win32.Core.ReleaseDC(myHandle, myHdc);
myHdc = IntPtr.Zero;

if (myBmp != null)
{
myBmp.Dispose();
myBmp = null;
}

// Dispose Message Manager
myMsgWnd.Dispose();
myMsgWnd = null;
}
}

Do you have an idea with all code ?

Thanks

Best Regards


"<ctacke/>" wrote:

> Are you ever disposing myBmp? Are you ever actually running out of memory?
>
> -Chris
>
>
>
> "Freddyboy" <(E-Mail Removed)> wrote in message
> news:F49DDCAF-5BAC-4237-95A3-(E-Mail Removed)...
> > Hi Alex, Hi Sergey
> >
> > yes I can show my code of course.
> >
> > [DllImport("coredll.dll", SetLastError=true)]
> > public static extern bool CloseHandle(IntPtr hObject);
> > ...
> > // get an handle to a bitmap
> > IntPtr hBitmap;
> > hBitmap = NDCaptureUtility.CreateGreyImageInDeviceContext(myHdc);
> > ....
> > // create bitmap with an handle
> > myBmp = BitmapBuffer.FromHbitmap(hBitmap);
> > ...
> > // delete handle (unmanaged ressource) with close handle
> > CloseHandle(hBitmap); // the value which is return is false
> >
> > // That's why I used DeleteObject
> > DeleteObject(hBitmap);
> >
> > But when I analyse Memory with Majerus's tools (www.phm.lu), I can see the
> > memory is more and more used.
> >
> > I think my problem is hBitmap.
> >
> > CreateGreyImageInDeviceContext is a method which is in a C Dll. There are
> > some methods which send some messages and with methods I can perform a
> > preview and I can take some pictures. Maybe a problem with unmaneged
> > Window
> > Message ? I know also compact framework service pack 3 which correct some
> > bugs with the marshalling between C# and C
> >
> > What do you think about this ?
> >
> > Thanks
> >
> > Best Regards.
> >
> > Fred
> >
> >
> >
> > "Alex Yakhnin [MVP]" wrote:
> >
> >> Which handle are you trying to de-allocate?
> >>
> >> Could you show your code?
> >> --
> >> Alex Yakhnin, .NET CF MVP
> >> www.intelliprog.com | www.opennetcf.org
> >>
> >>
> >> "Freddyboy" wrote:
> >>
> >> > Hi,
> >> >
> >> > I have an handle on a bitmap (FromHBitmap by Alex Yakhnin).
> >> > I'd like to close this handle with CloseHandle Method in core.dll but
> >> > it
> >> > seems to me that method has no effect.
> >> >
> >> > I use DeleteObject but it seems to me there are small memory leaks...
> >> >
> >> > How can I do ?
> >> >
> >> > Thanks
> >> >
> >> > Best Regards
>
>
>

Do you actually run out of memory, or are you simply seeing usage increase?

--
Chris Tacke
Co-founder
OpenNETCF.org
Has OpenNETCF helped you? Consider donating to support us!
http://www.opennetcf.org/donate


"Freddyboy" <(E-Mail Removed)> wrote in message
news:A65FBE3C-3278-41BF-8936-(E-Mail Removed)...
>I perform a dispose on myBmp and I dispose also myHdc.
> Complete Code:
> // Constructor
> public NDImager()
> {
> // Get form handle
> myHandle = GetActiveWindow();
> if (myHandle != IntPtr.Zero)
> {
> // get handle device context
> myHdc = OpenNETCF.Win32.Core.GetDC(myHandle);
> // build a NDImagerMessageWindow object
> myMsgWnd = new NDImagerMessageWindow(this);
> }
> }
>
> // An other Method which used myBmp, myHdc ...
> // this code is in a switch
> // I think it's here there is a problem with memory
>
> // get an handle to a bitmap
> IntPtr hBitmap;
> hBitmap = NDCaptureUtility.CreateGreyImageInDeviceContext(myHdc);
>
> // delete last bitmap
> if (myBmp != null)
> {
> myBmp.Dispose();
> myBmp = null;
> }
>
> // if handle is not null
> if (hBitmap != IntPtr.Zero)
> {
> // create bitmap with an handle
> myBmp = NDBitmapBuffer.FromHbitmap(hBitmap);
> // display bitmap
> myPictureBox.Image = myBmp;
> myPictureBox.Invalidate();
>
> // delete handle (unmanaged ressource)
> // the value which is returned by closehandle is false that's why I use
> DeleteObject
> DeleteObject(hBitmap);
> }
> protected void Dispose(bool disposing)
> {
> if (disposing)
> {
> // Stop Window Message
> StopRunningWithMessageWnd();
> Thread.Sleep(500);
>
> // Remember to release the device context
> OpenNETCF.Win32.Core.ReleaseDC(myHandle, myHdc);
> myHdc = IntPtr.Zero;
>
> if (myBmp != null)
> {
> myBmp.Dispose();
> myBmp = null;
> }
>
> // Dispose Message Manager
> myMsgWnd.Dispose();
> myMsgWnd = null;
> }
> }
>
> Do you have an idea with all code ?
>
> Thanks
>
> Best Regards
>
>
> "<ctacke/>" wrote:
>
>> Are you ever disposing myBmp? Are you ever actually running out of
>> memory?
>>
>> -Chris
>>
>>
>>
>> "Freddyboy" <(E-Mail Removed)> wrote in message
>> news:F49DDCAF-5BAC-4237-95A3-(E-Mail Removed)...
>> > Hi Alex, Hi Sergey
>> >
>> > yes I can show my code of course.
>> >
>> > [DllImport("coredll.dll", SetLastError=true)]
>> > public static extern bool CloseHandle(IntPtr hObject);
>> > ...
>> > // get an handle to a bitmap
>> > IntPtr hBitmap;
>> > hBitmap = NDCaptureUtility.CreateGreyImageInDeviceContext(myHdc);
>> > ....
>> > // create bitmap with an handle
>> > myBmp = BitmapBuffer.FromHbitmap(hBitmap);
>> > ...
>> > // delete handle (unmanaged ressource) with close handle
>> > CloseHandle(hBitmap); // the value which is return is false
>> >
>> > // That's why I used DeleteObject
>> > DeleteObject(hBitmap);
>> >
>> > But when I analyse Memory with Majerus's tools (www.phm.lu), I can see
>> > the
>> > memory is more and more used.
>> >
>> > I think my problem is hBitmap.
>> >
>> > CreateGreyImageInDeviceContext is a method which is in a C Dll. There
>> > are
>> > some methods which send some messages and with methods I can perform a
>> > preview and I can take some pictures. Maybe a problem with unmaneged
>> > Window
>> > Message ? I know also compact framework service pack 3 which correct
>> > some
>> > bugs with the marshalling between C# and C
>> >
>> > What do you think about this ?
>> >
>> > Thanks
>> >
>> > Best Regards.
>> >
>> > Fred
>> >
>> >
>> >
>> > "Alex Yakhnin [MVP]" wrote:
>> >
>> >> Which handle are you trying to de-allocate?
>> >>
>> >> Could you show your code?
>> >> --
>> >> Alex Yakhnin, .NET CF MVP
>> >> www.intelliprog.com | www.opennetcf.org
>> >>
>> >>
>> >> "Freddyboy" wrote:
>> >>
>> >> > Hi,
>> >> >
>> >> > I have an handle on a bitmap (FromHBitmap by Alex Yakhnin).
>> >> > I'd like to close this handle with CloseHandle Method in core.dll
>> >> > but
>> >> > it
>> >> > seems to me that method has no effect.
>> >> >
>> >> > I use DeleteObject but it seems to me there are small memory
>> >> > leaks...
>> >> >
>> >> > How can I do ?
>> >> >
>> >> > Thanks
>> >> >
>> >> > Best Regards
>>
>>
>>

Hi Chris,

I just see a usage increase.

Thanks.

"Chris Tacke, eMVP" wrote:

> Do you actually run out of memory, or are you simply seeing usage increase?
>
> --
> Chris Tacke
> Co-founder
> OpenNETCF.org
> Has OpenNETCF helped you? Consider donating to support us!
> http://www.opennetcf.org/donate
>
>
> "Freddyboy" <(E-Mail Removed)> wrote in message
> news:A65FBE3C-3278-41BF-8936-(E-Mail Removed)...
> >I perform a dispose on myBmp and I dispose also myHdc.
> > Complete Code:
> > // Constructor
> > public NDImager()
> > {
> > // Get form handle
> > myHandle = GetActiveWindow();
> > if (myHandle != IntPtr.Zero)
> > {
> > // get handle device context
> > myHdc = OpenNETCF.Win32.Core.GetDC(myHandle);
> > // build a NDImagerMessageWindow object
> > myMsgWnd = new NDImagerMessageWindow(this);
> > }
> > }
> >
> > // An other Method which used myBmp, myHdc ...
> > // this code is in a switch
> > // I think it's here there is a problem with memory
> >
> > // get an handle to a bitmap
> > IntPtr hBitmap;
> > hBitmap = NDCaptureUtility.CreateGreyImageInDeviceContext(myHdc);
> >
> > // delete last bitmap
> > if (myBmp != null)
> > {
> > myBmp.Dispose();
> > myBmp = null;
> > }
> >
> > // if handle is not null
> > if (hBitmap != IntPtr.Zero)
> > {
> > // create bitmap with an handle
> > myBmp = NDBitmapBuffer.FromHbitmap(hBitmap);
> > // display bitmap
> > myPictureBox.Image = myBmp;
> > myPictureBox.Invalidate();
> >
> > // delete handle (unmanaged ressource)
> > // the value which is returned by closehandle is false that's why I use
> > DeleteObject
> > DeleteObject(hBitmap);
> > }
> > protected void Dispose(bool disposing)
> > {
> > if (disposing)
> > {
> > // Stop Window Message
> > StopRunningWithMessageWnd();
> > Thread.Sleep(500);
> >
> > // Remember to release the device context
> > OpenNETCF.Win32.Core.ReleaseDC(myHandle, myHdc);
> > myHdc = IntPtr.Zero;
> >
> > if (myBmp != null)
> > {
> > myBmp.Dispose();
> > myBmp = null;
> > }
> >
> > // Dispose Message Manager
> > myMsgWnd.Dispose();
> > myMsgWnd = null;
> > }
> > }
> >
> > Do you have an idea with all code ?
> >
> > Thanks
> >
> > Best Regards
> >
> >
> > "<ctacke/>" wrote:
> >
> >> Are you ever disposing myBmp? Are you ever actually running out of
> >> memory?
> >>
> >> -Chris
> >>
> >>
> >>
> >> "Freddyboy" <(E-Mail Removed)> wrote in message
> >> news:F49DDCAF-5BAC-4237-95A3-(E-Mail Removed)...
> >> > Hi Alex, Hi Sergey
> >> >
> >> > yes I can show my code of course.
> >> >
> >> > [DllImport("coredll.dll", SetLastError=true)]
> >> > public static extern bool CloseHandle(IntPtr hObject);
> >> > ...
> >> > // get an handle to a bitmap
> >> > IntPtr hBitmap;
> >> > hBitmap = NDCaptureUtility.CreateGreyImageInDeviceContext(myHdc);
> >> > ....
> >> > // create bitmap with an handle
> >> > myBmp = BitmapBuffer.FromHbitmap(hBitmap);
> >> > ...
> >> > // delete handle (unmanaged ressource) with close handle
> >> > CloseHandle(hBitmap); // the value which is return is false
> >> >
> >> > // That's why I used DeleteObject
> >> > DeleteObject(hBitmap);
> >> >
> >> > But when I analyse Memory with Majerus's tools (www.phm.lu), I can see
> >> > the
> >> > memory is more and more used.
> >> >
> >> > I think my problem is hBitmap.
> >> >
> >> > CreateGreyImageInDeviceContext is a method which is in a C Dll. There
> >> > are
> >> > some methods which send some messages and with methods I can perform a
> >> > preview and I can take some pictures. Maybe a problem with unmaneged
> >> > Window
> >> > Message ? I know also compact framework service pack 3 which correct
> >> > some
> >> > bugs with the marshalling between C# and C
> >> >
> >> > What do you think about this ?
> >> >
> >> > Thanks
> >> >
> >> > Best Regards.
> >> >
> >> > Fred
> >> >
> >> >
> >> >
> >> > "Alex Yakhnin [MVP]" wrote:
> >> >
> >> >> Which handle are you trying to de-allocate?
> >> >>
> >> >> Could you show your code?
> >> >> --
> >> >> Alex Yakhnin, .NET CF MVP
> >> >> www.intelliprog.com | www.opennetcf.org
> >> >>
> >> >>
> >> >> "Freddyboy" wrote:
> >> >>
> >> >> > Hi,
> >> >> >
> >> >> > I have an handle on a bitmap (FromHBitmap by Alex Yakhnin).
> >> >> > I'd like to close this handle with CloseHandle Method in core.dll
> >> >> > but
> >> >> > it
> >> >> > seems to me that method has no effect.
> >> >> >
> >> >> > I use DeleteObject but it seems to me there are small memory
> >> >> > leaks...
> >> >> >
> >> >> > How can I do ?
> >> >> >
> >> >> > Thanks
> >> >> >
> >> >> > Best Regards
> >>
> >>
> >>
>
>
>