C / C++ / MFC

Re: return value CoCreateInstance not documented in MSDN [modified]

4-Aug-07 20:00

Hello everyone,

The return value of CoCreateInstance is -2146232576, which is un-documented in MSDN.

http://msdn2.microsoft.com/en-us/library/ms686615.aspx

What does it mean? What is wrong with my code?

<br />
HRESULT hr = CoCreateInstance(CLSID_MyDriver,<br />
			NULL,<br />
			CLSCTX_INPROC_SERVER,<br />
			IID_IMyDriver,<br />
			reinterpret_cast<void**>(&driver_interface));<br />
<br />
if (FAILED(hr))<br />
{<br />
	if (hr == REGDB_E_CLASSNOTREG)<br />
	{<br />
		printf("Couldn't create the instance!... 0x%x\n", hr);<br />
	}<br />
	else if (hr == CLASS_E_NOAGGREGATION)<br />
	{<br />
		printf("Couldn't create the instance!... 0x%x\n", hr);<br />
	}<br />
	else if (hr == E_NOINTERFACE)<br />
	{<br />
		printf("Couldn't create the instance!... 0x%x\n", hr);<br />
	}<br />
	else if (hr == S_OK)<br />
	{<br />
		printf("Couldn't create the instance!... 0x%x\n", hr);<br />
	}<br />
	else<br />
	{<br />
		printf("Couldn't create the instance!... 0x%x\n", hr);<br />
	}<br />
}<br />

thanks in advance,
George

Mark Salsbery4-Aug-07 20:48

Re: return value CoCreateInstance not documented in MSDN

4-Aug-07 20:48

Interesting error Smile | :)

Maybe some clues here[^]

That's the most I could find.

MArk

*edit* fixed link

Last modified: 12mins after originally posted --

Mark Salsbery
Microsoft MVP - Visual C++
Java | [Coffee]

George_George4-Aug-07 21:02

Re: return value CoCreateInstance not documented in MSDN

4-Aug-07 21:02

Thanks Mark,

I have tried to register into GAC, but the error message is still the same. Any ideas?

regards,
George

bob169725-Aug-07 17:19

bob16972

5-Aug-07 17:19

/* Try putting your CLSID and GUID in there
and see if this gets you going
*/

IMyDriver driver_interface;

// Class ID (GUID)
IID IID_IMyDriver;
::IIDFromString(L"{12345678-1234-1234-1234-123456789012}",
&IID_IDriver_Interface);
// CLSID
CLSID CLSID_IMydriver;
::CLSIDFromString(L"{98765432-9876-9876-9876-987654321098}",
&CLSID_MyDriver);

// When using CoCreateInstance
hr=CoCreateInstance(CLSID_IMydriver,NULL,CLSCTX_INPROC_SERVER,
IID_IMyDriver,(void**)&driver_interface);

if (SUCCEEDED(hr)) {
// Do something with driver_interface
}

Re: return value CoCreateInstance not documented in MSDN

George_George5-Aug-07 18:05

Re: return value CoCreateInstance not documented in MSDN

5-Aug-07 18:05

Thanks bob16972,

I have tried your new method, but the error is the same. I suspect the DLL (which implements MyDriver class) is not loaded correctly. Do you think so? What is the check list?

regards,
George

bob169725-Aug-07 21:06

bob16972

5-Aug-07 21:06

Here are some ideas/questions based on past experiences with COM...

When you register/unregister the dll using "regsvr32.exe" from a "cmd" window, what message do you get?

Have you verified that the item shows up in "OLE View"? If you are using Visual C++ 6.0, "OLE View" is in the "Microsoft Visual C++ 6.0 Tools" in the program list.

You can also search HKCR (HKEY_CLASSES_ROOT) to verify the ProgID, CLSID, and classes are all there.

How did you create your MyDriver class in Visual C++?

Did you verify the CLSID and the class GUID are correct in your code? Always copy and paste them from "OLE View" to avoid any miskeying when not using the ProgID.

Re: return value CoCreateInstance not documented in MSDN

George_George5-Aug-07 21:14

how to pass a structure as reference. [modified]

5-Aug-07 21:14

Thanks bob16972,

I have tried to write an executable and using the same code to utilize the function from the COM component, it works!

Previously, I wrote a COM (C++ unmanaged code), and use the C++ COM invokes another function from a C# COM (managed code), and it fails -- this is what I described at the beginning of this question -- "return value CoCreateInstance not documented in MSDN".

Any ideas? Why exe as a client works but DLL as a client does not work?

regards,
George

uday kiran janaswamy4-Aug-07 19:49

uday kiran janaswamy

4-Aug-07 19:49

Hi all,

i am facing a problem while passing a reference as structure from one class member function to another class member function.

ie) i will pass a struct as input from Class A member function
to Class B member function. There in Class B member function
it has to fill the Structure and give me the filled structure
in Class A member function.

Note: this i am facing in vc++. i am having two dialog classes where i have to send this reference variable from first class member function to second Class member function.

please this very very urgent for me.

-- modified at 1:57 Sunday 5th August, 2007

Uday kiran

Mark Salsbery4-Aug-07 20:54

4-Aug-07 20:54

Can you show an example of the method declaration and how you were calling it?

What exactly is the problem that's occurring?

Mark

Mark Salsbery
Microsoft MVP - Visual C++
Java | [Coffee]

Legolas655-Aug-07 3:41

Legolas65

5-Aug-07 3:41

Either you pass the member function a pointer to the structure (&structvar), or make the receiving function accept the argument by reference (classname::member(structtype & structvar).

uday kiran janaswamy6-Aug-07 3:05

uday kiran janaswamy

6-Aug-07 3:05

hi,

Thanks a Lot I get it.

Uday kiran

bob169725-Aug-07 5:11

bob16972

5-Aug-07 5:11

/* Not dialog based but you should get what your
looking for here.
*/

#include "stdafx.h"
#include <stdio.h>

typedef struct
{
int nKey;
int nSize;
} MY_STRUCTURE;

class CBar
{
public:
CBar::CBar() {}
CBar::~CBar() {}

void CBar::DoSomething(MY_STRUCTURE& myStructure)
{
// Modify the structure
myStructure.nKey=45;
myStructure.nSize=99;
}
};

class CFoo
{
public:
CFoo()
{
Start();
}

~CFoo() {}

void Start()
{
CBar bar;
MY_STRUCTURE someStructure={0};

printf("BEFORE: nKey = %d, nSize = %d\n",
someStructure.nKey,someStructure.nSize);

bar.DoSomething(someStructure);

printf("AFTER: nKey = %d, nSize = %d\n",
someStructure.nKey,someStructure.nSize);
}
};

int main(int argc, char* argv[])
{
CFoo foo;

return 0;
}

uday kiran janaswamy6-Aug-07 3:03

uday kiran janaswamy

6-Aug-07 3:03

hi,

Yes, i cought for this only and you have showed me path.

Thanks a Lot it exaclty what the problem i facing.

Uday kiran

list.remove removes all the list

ThatsAlok5-Aug-07 19:51

ThatsAlok

5-Aug-07 19:51

uday kiran janaswamy wrote:
Note: this i am facing in vc++. i am having two dialog classes where i have to send this reference variable from first class member function to second Class member function.

But what is the problem!.. hang, value is not updated or something else!

"Opinions are neither right nor wrong. I cannot change your opinion. I can, however, change what influences your opinion." - David Crow

cheers,
Alok Gupta
VC Forum Q&A :- I/ IV
Support CRY- Child Relief

beriho4-Aug-07 18:25

beriho

4-Aug-07 18:25

hi all;

when i invoke the method below it delets all my objects from the list, can any one please tell me what i am doing wrong?
if there are 3 objects in the list and i am asking to delete the last one, it moves over all of the items but when it deletes the 3rd, it deletes them all..

thanks a lot,

Beri

bool cListAdv::remOneFromList ( long _unqAdvName )
{
if ( ListOfAdv.size() == 0 )
{
return false; // empty list
}
else
{
list<cAdv>::iterator iter ;

iter = ListOfAdv.begin() ; // set the iter to the begining of the list

while ( iter != ListOfAdv.end() ) // if it is not the end continue to check
{
cAdv tempAdv(*iter); // define a temporary adv and set it to the first object

//if (ListOfAdv.size() == 1 ) iter++; // change before deleting the same object - prevent mem error
iter++;
if ( tempAdv.getUnqAdvName() == _unqAdvName )
{
//ListOfAdv.remove( *iter ) ; // if they have the same AdvId remove - removes all objects from list
ListOfAdv.remove( tempAdv );
return true;
}
//++iter;
}
return false ; // not found
}
}

Re: list.remove removes all the list

C^hris L^osinger5-Aug-07 10:52

C^hris L^osinger

5-Aug-07 10:52

does cAdv have an == operator ?

lst.remove(x) deletes items from lst which match the value 'x'.

image processing toolkits | batch image processing | blogging

Re: list.remove removes all the list

beriho5-Aug-07 19:38

beriho

5-Aug-07 19:38

yes it does,

but it checks a different value;
can list.erase do the job instead?

May The Force Be With You...

Stop list view items from being sorted

Perspx4-Aug-07 11:20

Perspx

4-Aug-07 11:20

Is there a way to stop items in a list view report style from being sorted alphabetically when they are inserted using the Win32 API?

Thanks for your help!
--PerspX

"Nowadays, security guys break the Mac every single day. Every single day, they come out with a total exploit, your machine can be taken over totally. I dare anybody to do that once a month on the Windows machine." - Bill Gates

Mark Salsbery4-Aug-07 11:52

4-Aug-07 11:52

Don't specify the LVS_SORTASCENDING or LVS_SORTDESCENDING when creating the control?

Mark

Mark Salsbery
Microsoft MVP - Visual C++
Java | [Coffee]

Perspx4-Aug-07 11:53

Perspx

4-Aug-07 11:53

I havent done that.. I've just created the control with WS_VISIBLE, WS_CHILD and LVS_REPORT.. Then I've set the Extended style to LVS_EX_FULLROWSELECT

--PerspX

Mark Salsbery4-Aug-07 12:09

4-Aug-07 12:09

Hmmm I can't reproduce that.

Mark

Mark Salsbery
Microsoft MVP - Visual C++
Java | [Coffee]

Hamid_RT4-Aug-07 19:21

Hamid_RT

4-Aug-07 19:21

Did you make it or use of toolbox?

WhiteSky