Hi,
Lets say I write this line:
BSTR b = m_pdoc->Getxml ();
where m_pdoc is MSXML2::IXMLDOM DocumentPtr.
Now "b" contains the xml text. When I exit the function in which this line
is written, do I have to take care about deleting "b"? And how do I do it ?
Regards,
-Ab. 4 6104
Lets say I write this line:
BSTR b = m_pdoc->Getxml ();
where m_pdoc is MSXML2::IXMLDOM DocumentPtr.
Now "b" contains the xml text. When I exit the function in which this line
is written, do I have to take care about deleting "b"? And how do I do it
?
Hi,
You can use use SysFreeString for that.
Or you could use _bstr_t instead of BSTR.
It is a wrapper around BSTR, and it will do those things for you
--
Kind regards,
Bruno van Dooren br************* *********@hotma il.com
Remove only "_nos_pam"
wow , cool.
-Ab.
"Bruno van Dooren [MVP VC++]" <br************ **********@hotm ail.comwrote
in message news:OT******** *****@TK2MSFTNG P02.phx.gbl...
Lets say I write this line:
BSTR b = m_pdoc->Getxml ();
where m_pdoc is MSXML2::IXMLDOM DocumentPtr.
Now "b" contains the xml text. When I exit the function in which this
line
is written, do I have to take care about deleting "b"? And how do I do
it
?
Hi,
You can use use SysFreeString for that.
Or you could use _bstr_t instead of BSTR.
It is a wrapper around BSTR, and it will do those things for you
--
Kind regards,
Bruno van Dooren br************* *********@hotma il.com
Remove only "_nos_pam"
Hi Abubakar,
Lets say I write this line:
BSTR b = m_pdoc->Getxml ();
where m_pdoc is MSXML2::IXMLDOM DocumentPtr.
Now "b" contains the xml text. When I exit the function in which this
line is written, do I have to take care about deleting "b"? And how do
I do it ?
Actually, I believe your code is incorrect. IXMLDOMDocument Ptr is a compiler-generated
wrapper for the raw COM interface, and does not return a BSTR, but a _bstr_t.
By assigning the return value to a BSTR, you are invoking a conversion operator
on the returned _bstr_t, which is subsequently destroyed. Your b variable
is essentially pointing to random memory.
If you are going to use the wrappers generated by #import, prefer the wrapper
types to the raw automation types, and do something like this:
_bstr_t b = m_pdoc->Getxml();
// b can now be used safely until it goes out of scope
_bstr_t deallocates the contained string in its destructor, so you generally
don't need to worry about any deallocation.
--
Best Regards,
Kim Gräsman
Actually, I believe your code is incorrect. IXMLDOMDocument Ptr is a
compiler-generated
you are right but in my case it was working just fine.
If you are going to use the wrappers generated by #import, prefer the
wrapper
types to the raw automation types, and do something like this:
_bstr_t b = m_pdoc->Getxml();
// b can now be used safely until it goes out of scope
_bstr_t deallocates the contained string in its destructor, so you
generally
don't need to worry about any deallocation.
Understood.
Thanks.
-ab.
"Kim Gräsman" <ki*@mvps.orgwr ote in message
news:45******** *************** ***@news.micros oft.com...
Hi Abubakar,
Lets say I write this line:
BSTR b = m_pdoc->Getxml ();
where m_pdoc is MSXML2::IXMLDOM DocumentPtr.
Now "b" contains the xml text. When I exit the function in which this
line is written, do I have to take care about deleting "b"? And how do
I do it ?
Actually, I believe your code is incorrect. IXMLDOMDocument Ptr is a
compiler-generated
wrapper for the raw COM interface, and does not return a BSTR, but a
_bstr_t.
>
By assigning the return value to a BSTR, you are invoking a conversion
operator
on the returned _bstr_t, which is subsequently destroyed. Your b variable
is essentially pointing to random memory.
If you are going to use the wrappers generated by #import, prefer the
wrapper
types to the raw automation types, and do something like this:
_bstr_t b = m_pdoc->Getxml();
// b can now be used safely until it goes out of scope
_bstr_t deallocates the contained string in its destructor, so you
generally
don't need to worry about any deallocation.
--
Best Regards,
Kim Gräsman
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