Re: IXMLDOMDocumentPtr instance destruction
On 23 May 2006 07:43:51 -0700, "sandy" <srpasham@gmail.com> wrote:
I have created an instance of IXMLDOMDocumentPtr
//Create DOM Instance
HRESULT hResult =
m_plDomDocument.CreateInstance(MSXML2::CLSID_DOMDocument);
if (FAILED(hResult)||(NULL == m_plDomDocument))
{
bRet = FALSE;
LEAVE_BLOCK
}
After this line gets executed the Handle count ( In Task Manager) gets
incremented by 18 ( from 237 to 255). The handle count never gets
decremented even after I come out of the dll.
Not sure what "come out of the dll" means, or what all the BEGIN_BLOCK,
END_BLOCK, and LEAVE_BLOCK macros do.
How can I release or destroy the DOM instances in the destructor.
It ought to be done automatically when the object containing
m_plDomDocument is destroyed.
Is there any alternate way to bring the handle count back to where its
started.
Unless you are observing the handle count to grow every time you create and
destroy an IXMLDOMDocumentPtr, I wouldn't worry about it; it could just be
some housekeeping internal to COM.
I would greatly appreciate if some one help me out.
Here is the function
bool CJobXMLParser::InitXMLFile(const string& strFilename)
{
bool bRet = TRUE;
BEGIN_BLOCK
if (NULL != m_plDomDocument)
{
CloseXMLFile();
}
m_szFolderName = "";
m_szSubFolderName = "";
m_szFileName = strFilename.c_str();
// convert xml file name string to something COM can handle (BSTR)
_bstr_t bstrFileName(m_szFileName);
//Create DOM Instance
HRESULT hResult =
m_plDomDocument.CreateInstance(MSXML2::CLSID_DOMDocument);
if (FAILED(hResult)||(NULL == m_plDomDocument))
{
bRet = FALSE;
LEAVE_BLOCK
}
// call the IXMLDOMDocumentPtr's load() to load the XML document
//variant_t vResult;
_variant_t vtFileName(_bstr_t(strFilename.c_str()));
bRet = m_plDomDocument->load(vtFileName);
// success!
if (bRet)
{
// Initialize the root pointer
m_pDocRoot = m_plDomDocument->documentElement;
if(NULL == m_pDocRoot)
{
bRet = FALSE;
LEAVE_BLOCK
}
}
END_BLOCK
return bRet;
}
If you want m_plDomDocument to release its instance upon return from this
function, you can set it to NULL or call Release on it. To do this
automatically, you should use RAII, but if m_plDomDocument is to be created
and destroyed inside this function, it shouldn't be a member variable
anyway; it should just be an ordinary local variable, and then RAII takes
care of itself.
--
Doug Harrison
Visual C++ MVP