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For using Smart Pointer, it'll handle all reference counting for me. However, for some cases, I couldn't use it.
Can anyone tell me the following functions if AddRef() is called automatically, or I should call it explicitly.
1. CComObject<t>::CreateInstance()
2. CComObject<t>::QueryInstance()
3. CoCreateInstance()
4. SmartPtr->CreateInstance() -- (i supposed addref-ed auto)
5. SmartPtr->QueryInterface() -- (i supposed addref-ed auto)
6. pUnknown->QueryInterface()
I see from many samples, the codes are just called CoCreateInstance() or pUnknown->QueryInterface() to return the pointer directly without calling AddRef(). It will do automatically ?
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All of those functions call add ref before returning the pointer.
QueryInterface calls Addref internally before returning the new interface that you are querying.
CComObject::CreateInstance calls CoCreateInstance, which internally calls QueryInterface.
Are you having any particular problems, or are you just making sure?
Build a man a fire, and he will be warm for a day
Light a man on fire, and he will be warm for the rest of his life!
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I tried CComObject::CreateInstance is not calling CoCreateInstance, it just called new only.
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You are right about CComObject::CreateInstance, I forgot this is the function that creates the object in ATL. However, I still beleive that it calls Query Interface so I think you should still be safe with this function.
Build a man a fire, and he will be warm for a day
Light a man on fire, and he will be warm for the rest of his life!
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I need to create Dll in VC++.I created a Dll using the option Win32 Dynamic Link Library from the options and added a .def file to mention the functions exproted by the Dll.Now I want to get my Dll registered.I used the command regsvr32 Dllfilename.dll.But instead of registering a message is popped up saying ::-
Dllfilename.dll was loaded,but the DllRegisterServer entry point was not found.
DllRegisterServer may not be exported,or a corrupt version of Dllfilename.dll may be in memory.Consider using Pview to detect and remove it.
I'm not able to trace the error.Can anybody help??
Abhishek.
Learning is a never ending process of Life.
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You only need to register your DLL if it contains a COM server.
If you have simply created a DLL that exports a few API functions, then you do not need to call regsvr32.
If you want to use that DLL in another program you can call LoadLibrary then GetProcAddress to create a function pointer to the functions that you have exported from you DLL.
Or if you want to statically link your DLL to another program you can link your program to the .lib file that is created in the DLL, and that will allow you to simply call the function directly in your code.
Build a man a fire, and he will be warm for a day
Light a man on fire, and he will be warm for the rest of his life!
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hi all,
i want to know how can i get my current ip in a pc? any API to acheive this?
thanks,
jim
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#include <winsock2.h>
DWORD InitWinSock()
{
WSADATA data;
if (WSAStartup(MAKEWORD(2, 2), &data) != 0)
return WSAGetLastError();
return 0;
}
DWORD GetIpAddress(LPCTSTR lpszHost, LPSTR ip)
{
LPHOSTENT lphost;
lphost = gethostbyname(lpszHost);
if (lphost == NULL)
{
*ip = NULL;
return WSAGetLastError();
}
SOCKADDR_IN sockAddr;
sockAddr.sin_addr.s_addr = ((LPIN_ADDR)lphost->h_addr)->s_addr;
strcpy(ip,inet_ntoa(sockAddr.sin_addr));
return 0;
}
void main()
{
InitWinSock();
char szHost[256];
gethostname(szHost,sizeof(szHost));
char ip[16];
GetIpAddress(szHost,ip);
}
don't forget to link with Ws2_32.lib.
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In script engine, I can use IActiveScript->AddNamedItem() to add a root level item. But how to add a 2nd level named item ?
I can add the root level "Application", but I don't know how to add a second level "Documents" to "Application".
Does anyone know ?
Is it only first level item can have event ?
Thanks
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The second level is accessible via the first levels IDispatch interface - i.e. if you have a Documents property, you could use Application.Documents in script. The script engine uses your IActiveScriptSite interface to get Application, then calls into Application to get Documents.
As for events...I believe the following should work (I'm assuming VBScript and an event called DoSomething)
Dim event_raiser
Sub event_raiser_DoSomething
some code
End Sub
Set event_raiser = Application.Documents
some more code, which causes DoSomething to be raised
I think you can handle events from any object you can reference like that. I'm not sure how you hook up events in JScript, but I guess the same is true.
<after looking @ MSDN>
It appears you can use a function of the form object_variable_name::event_name (which is like the VB example above) or something like object.event = function pointer, which I've never used, but sounds like it doesn't use
IConnectionPoint et. al. I'm not sure - does anyone know for sure?<br />
<code></after looking @ MSDN>
Stuart Dootson
'Java, Basic, who cares - it's all a bunch of tree-hugging hippy cr*p'
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I am successfully conecting to *.mdb database on my local machine using following connection string:
HRESULT hr = m_pConnection->Open(
_bstr_t(L"Provider=Microsoft.Jet.OLEDB.4.0;Data Source=c:\\source\\VCDb.mdb;"),
_bstr_t(L""),
_bstr_t(L""),
NULL);
Now i want to connect to SQL-Server running on the machine in my neighbourhood. The ip of target machine is 192.168.10.10. Plz tell me the connection string.
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I don't know whether this is a correct forum to ask this question..Anyways.
I place certain font file in the windows fonts directory. It gets automatically register in the registry. At that time my application and other applications properly loads the font. But sometimes font automatically disappeaared both from fonts directory and registry especially when i restart my computer. Sometime when i refresh the fonts folder, the font appears again and related applications starts loading it normally. Can anyone tell me whats the problem
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I have a char* buffer pBuf filled with a bitmap. I want to get the size of the bmp from this buffer so I see that I need stuff like:
BITMAPINFOHEADER &bmiHeader = *(LPBITMAPINFOHEADER)(what goes here?);
BITMAPINFO &bmInfo = *(LPBITMAPINFO)(what goes here?);
Thanks,
ns
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pBuf
WWJD? JWRTFM.
found on /.
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hello all (incl chris L  )
i have a popup menu in my sdi app...and this popup gets generated dynamically...full of all sorts of goodies and can get quite big
my quesiton is this:
where do i catch all messages from this menu ? so i can then figure out which one it was
- i can't prefine all the windows commands before the menu as the menu is built from a search on a database
cheers and thanks
Bryce
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(hey  )
when you build the menu, i assume you're adding menu items with InsertMenu ? if you are, then you are probably providing a "command ID" as one of the parameters. that ID is what you need to handle (and you should be using IDs you created with the Resource Symbols menu).
so, in whatever window you want to handle the message, add a line like this to the .cpp's MESSAGE_MAP
ON_COMMAND(ID_MY_MENU_ID, MyHandler)
add a line like this to the .h:
afx_msg void MyHandler();
then write the "void CMyVest::MyHandler()" function
-c
WWJD? JWRTFM.
found on /.
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yep thats cool and i knew dat
but i'd need one for each menu item
and theres no way of knowing at compile time how many there will be
i starts at abase of ID_BASE_SHORT_REF_COMMAND and increment for each item
do u see what i mean?
bryce
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ah, yeah that's a problem. you could always just allocate yourself a range of resource IDs in your resource.h file (like 2x as many as you think you'll ever need).
i am working on app right now that essentially does this. i reserved 100 items in resource.h (copy paste, edit, boring). at run time, i keep a std::map around that maps the arbitrary menu ID to a meaningful identifier which i set when i add the menu items. i only have one menu handler, and it just takes the last message ID, looks it up in the map and then proceeds accordingly, when the user chooses one.
WWJD? JWRTFM.
found on /.
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what about catching it in a pretranslatemsg function or something and seeing if its mroe than ID_BASE_SHORT_REF_COMMAND and less than ID_BASE_SHORT_REF_COMMAND+menuitems
?
Bryce
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yeah, i think that might work too. never know till you try 
-c
WWJD? JWRTFM.
found on /.
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erm why not do this
ofstream out;
out.open("i:\\test.txt");
for (int index =1; index <= 1000; index++)
{
CString temp ;
temp.Format("#define ID_SHORT_REF_MENU%d %d",index,34000+index);
out <
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yeah. i probably would've done the same, if i had a 1000 to do.
-c
Conservative:
One who admires radicals centuries after they're dead.
-- Leo C. Rosten
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shoudnt u be in bed? its bloody late in yankeeland isnt it?
bryce
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3:30 am.
zzz
i have a cool idea. i can't sleep!
-c
Conservative:
One who admires radicals centuries after they're dead.
-- Leo C. Rosten
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