ADO events biased to COM memory model? - COM Discussion Boards

GWENJi29-Apr-03 4:09

29-Apr-03 4:09

Have a compile time error. Trying to compile a COM object - when the compile gets to

"Linking...
Creating library Debug/C2PCGWSettings.lib and object Debug/C2PCGWSettings.exp
Registering ActiveX Control.."
Error reading key....

C2PCGWSettings.dll - 1 error(s), 0 warning(s)

Any ideas?
Thanks

Get [source] interface DISPID (id)

Abebe28-Apr-03 22:47

Abebe

28-Apr-03 22:47

Hi,

I'm kinda stuck at the moment so i hope some of you guys can help me out. Ok here's the question:

How can you get the method id's of a [default, source] interface using smart pointers only. It is not a dispinterface (since then you had to supply id's), but a normal interface which derives from IDispatch. I can't create an instance or query for the interface, because it's a [source] interface...right. So how can i get these id's.

Any help would be greatly appreciated.

Re: Get [source] interface DISPID (id)

Abebe29-Apr-03 1:30

Abebe

29-Apr-03 1:30

nevermind....already found it out myself.......but thanx for not replying though.

Whats the use for DECLARE_DISPATCH_MAP and DECLARE_OLECREATE_EX??

safee ullah28-Apr-03 22:35

safee ullah

28-Apr-03 22:35

hi there!

i wanted to know the EXACT purpose that The Macros DECLARE_DISPATCH_MAP and DECLARE_OLECREATE_EX do? WTF | :WTF:

and where are they used?

thanks...
&
regards
safee

COM Voodoo

vlvl28-Apr-03 21:06

vlvl

28-Apr-03 21:06

Hi, I wonder if anyone else stumbled on this problem - I have an ATL/COM server, which normally works just fine, being instantiated from both ASP and MFC projects.
However, once in a while, w/o any apparent reason, ::CoCreateInstance fails, returning "Class Not Registered". Usually a reboot and or rebuilding the COM component helps, but sometimes it doesnt.
Needless to say, that the class *is* registered, and can be seen using the OLE/COM Viewer.
Any ideas?

VL

Re: COM Voodoo

safee ullah29-Apr-03 0:56

safee ullah

29-Apr-03 0:56

check if the dll is already in use some where else in some other process...i think this should solve your problem....

regards

Re: COM Voodoo

Stephane Rodriguez.7-May-03 20:49

Stephane Rodriguez.

7-May-03 20:49

If your COM server happens to be a .exe, then be sure to know that by default IIS won't start more than 2 .exe COM instances.

ADO events biased to COM memory model?

Chopper28-Apr-03 9:31

Chopper

28-Apr-03 9:31

Hi All,

I’m handling events of ADO in an ATL out-of-process server, and for some reasons when I use _ATL_FREE_THREADED declaration event ConnectComplete is not called when I establish an asynchronous connection, thou it is called when I use a synchronous connection. Changing the memory model to _ATL_APARTMENT_THREADED solves the problem, but what is the reason of such strange behaviour anyway, and what’s the
proper solution?

Regards,
Vitaly Tomilov

COM interop to Outlook -- BeforeFolderSwitch

rkiesler27-Apr-03 3:57

rkiesler

27-Apr-03 3:57

I'm implementing a COM add-in for Outlook using C#. I have added an event handler to the Outlook.Explorer BeforeFolderSwitch event as follows:

m_activeExp.BeforeFolderSwitch += new Outlook.ExplorerEvents_10_BeforeFolderSwitchEventHandler( this.OnBeforeFolderSwitch );

The event handler method is as follows:

public void OnBeforeFolderSwitch( object newFolder, ref bool cancel )<br />
{<br />
   MAPIFolder oNewFolder = (MAPIFolder)newFolder;<br />
   if ( oNewFolder.Name.Equals( "Rhythmyx" ) )<br />
   {<br />
      if ( m_psSessionID == null || m_psSessionID.Trim().Equals( "" ) )<br />
      {<br />
         // pop the login dialog<br />
         LoginForm   loginForm = new LoginForm();<br />
         if ( loginForm.ShowDialog() == DialogResult.OK )<br />
         {<br />
            // TODO: ...<br />
         }<br />
         else<br />
         {<br />
            cancel = true;   // this should prevent the folder switch<br />
         }<br />
         loginForm.Dispose();<br />
      }<br />
   }<br />
}

The "cancel = true;" statement should prevent the folder switching, but for some reason, it does not. FWIW, I have the same code in a VBA module (prototype), and setting the cancel parameter to True indeed prevents the folder switch.

Any ideas why this is not behaving as expected?

Thanks,
--
Roy Unsure | :~

Re: COM interop to Outlook -- BeforeFolderSwitch

Stephane Rodriguez.7-May-03 20:52

Stephane Rodriguez.

7-May-03 20:52

May be a dummy note, but are you sure cancel = true; is executed ? (ref bool cancel is the right parameter signature, it should work!).

Re: COM interop to Outlook -- BeforeFolderSwitch

rkiesler9-May-03 5:32

rkiesler

9-May-03 5:32

Not a dummy note at all -- and thank you for the reply.

I am sure, and here's the call stack after I set cancel to true:

> rx5.dll!Rx5.Connect.OnBeforeFolderSwitch(System.Object newFolder = {System.__ComObject}, bool cancel = true) Line 221 C#

The only thing that makes me wandr is why the call stack does not show the cancel parameter as a ref parameter -- the method signature is as follows:

public void OnBeforeFolderSwitch( Object newFolder, ref bool cancel)

Could it be that the Outlook interop DLL somehow treats cancel as a value parameter?

I'd be more then happy to send me code for someone else to try it out.

--
Roy

2-D SafeArray

tomercagan26-Apr-03 10:10

tomercagan

26-Apr-03 10:10

I am trying to write a DLL to be called from VB. Thus I had to use SAFEARRAY.
I have a problem that when I am accessing all the elements in the array I can change their values but when I try to access a specific element it seems not to accept the new value I try to assign.

For example, I have these functions:

void Set2DSafeArrayPtr(SAFEARRAY * psaiInOut, long val)
{
long ai[2];
int x,y;
LRESULT hres;
int xMin = psaiInOut->rgsabound[0].lLbound;
int xMax = xMin + (int)psaiInOut->rgsabound[0].cElements - 1;
int yMin = psaiInOut->rgsabound[1].lLbound;
int yMax = yMin + (int)psaiInOut->rgsabound[1].cElements - 1;
// Set up dimension array and pointer to receive value.
long * piInOut;
if (hres = SafeArrayLock(psaiInOut)) throw hres;
for (x = xMin; x <= xMax; x++) {
ai[0] = x;
for (y = yMin; y <= yMax; y++) {
ai[1] = y;
hres = SafeArrayPtrOfIndex(psaiInOut, ai, (void **)&piInOut);
if (hres) throw hres;
// Equivalent to: aiInOut(x, y) = aiInOut(x, y) + 1.
(*piInOut) = val;
}
}
if (hres = SafeArrayUnlock(psaiInOut)) throw hres;
}

void SetElementPtr(SAFEARRAY * psaiInOut, int x, int y, long val)
{
LRESULT hres;
long * piInOut;
long ai[2];
if (hres = SafeArrayLock(psaiInOut)) throw hres;

ai[0] = x;
ai[1] = y;
hres = SafeArrayPtrOfIndex(psaiInOut, ai, (void **)&piInOut);
if (hres) throw hres;

(*piInOut) = val;

if (hres = SafeArrayUnlock(psaiInOut)) throw hres;
}

my program

void main{
...
SAFEARRAYBOUND bDim[2];
bDim[0].lLbound = 0;
bDim[0].cElements = 6;
bDim[1].lLbound = 0;
bDim[1].cElements = 6;

psaiNew = SafeArrayCreate(VT_I4, 2, bDim);
if(psaiNew == NULL){
cout << "Unable to initialize array. Not enough memory" << endl;
return;
}

hres = SafeArrayLock(psaiNew);

Set2DSafeArrayPtr(psaiNew, 15);
SetElementPtr(psaiNew, 1,2,30);

hres = SafeArrayUnlock(psaiNew);
...
}

The Set2DSafeArrayPtr seems to work fine but the SetElementPtr doesn't seem to work.

Any idea why? What am I doing wrong?
I'd also like to know of a good place I can find references/examples (other then MSDN)...

Re: 2-D SafeArray

Hans Ruck30-Apr-03 1:13

Hans Ruck

30-Apr-03 1:13

This code works fine in a MDI application. The error must come from somewhere else.

rechi

OLE DB problem in VC++ COM when used in ASP

Mahesh Perumal26-Apr-03 2:20

Mahesh Perumal

26-Apr-03 2:20

I have written a COM component in VC++ that connects to a ODBC (.mdb file) through OLE DB. When i try to use it in .asp page i get error (0x80004005 - unspecified error). The same component (same asp file) works fine with PWS under Win98. When i run the same with IIS5 in Win2000 and WinXP i get error. I couldn't find out what might be the problem. Can you help me out?

Thanx in advance
Mahesh

ne One Heard of CAutomationObject

safee ullah23-Apr-03 21:40

safee ullah

23-Apr-03 21:40

hi there..

thanks for your time first..
i wanted to know if you may have some source of information on what does the variable m_ObjectType does in the Class CAutomationObject does??

help is desparately needed..

thanks

regards
safee

What cause such link errors?

ray_li23-Apr-03 10:41

ray_li

23-Apr-03 10:41

I compiled and linked some sample source code got from Microsoft SDK, there were some strange link errors:"error LNK2001: unresolved external symbol "error LNK2001: unresolved external symbol "void * __cdecl operator new[](unsigned int)" (??_U@YAPAXI@Z)" and "error LNK2001: unresolved external symbol "void __cdecl operator delete[](void *)" (??_V@YAXPAX@Z)", it caused by such code:"_TCHAR *szName = new _TCHAR[100]" and "delete []szName".I tried to change the project setting option, but it still happened. I just wonder if there is anyone once met such problem before and how to solve it. Thank you.

Ray

Re: What cause such link errors?

Anonymous3-May-03 2:07

Anonymous

3-May-03 2:07

It seems like you have problems with unicode.
Are the settings OK for that?

_variant_t

Anthony_Yio21-Apr-03 19:42

Anthony_Yio

21-Apr-03 19:42

How to extract the content of the _variant_t if
the VARTYPE is VT_DISPATCH?

thank you

Re: _variant_t

Hans Ruck23-Apr-03 4:46

Hans Ruck

23-Apr-03 4:46

Cast it to LPDISPATCH.

rechi

Re: _variant_t

Renjith Ramachandran15-May-03 7:07

Renjith Ramachandran

15-May-03 7:07

ppdispVal

[ It is possible to represent everything in this universe by using 0 and 1 ]

How to catch new enent of OFFICE WORD

yanshiqi21-Apr-03 16:10

yanshiqi

21-Apr-03 16:10

I have project that is based MFC, in this project, i want to catch new event of Word in AutoMation, and now i can catch sample enent, such as "DocumentChange", "Quit", but i can't catch "DocumentOpen" "DocumentSelectChange" etc new event, why? please tell me
how to do, thanks a lot! Roll eyes | :rolleyes:

Hello everyone

Re: How to catch new enent of OFFICE WORD

Anonymous22-Apr-03 0:31

Anonymous

22-Apr-03 0:31

http://www.codeproject.com/com/adWordAddin.asp

Threads in COM

rattagarn18-Apr-03 1:16

rattagarn

18-Apr-03 1:16

Hi all,

Can I build ActiveX Control that implements the multithread features? What I means is the control that operate the background process and user can stop its operation.
Why do I need this control? It seems like a console UI control that I can key any commands on this control and then it sends the command to a hardware via serial comm port. After that the hardware send back data to buffer. The control reads back and display on the console. I found some difficulties on this model. If the hardware sends a long operation data, UI control is freezed, I can't key any commands to break it.

Thank you very much

champ

Re: Threads in COM

Imran_Farooqui18-Apr-03 1:23

Imran_Farooqui

18-Apr-03 1:23

Please read this article [^] before applying any threading work inside ActiveX control.

COM server location on CLSID

thowra17-Apr-03 23:30

thowra

17-Apr-03 23:30

Is there a simple way to determine the location of a COM server for a given CLSID?

I know that given a CLSID, I can convert to a string and look it up in the registry "HKEY_CLASSES_ROOT\CLSID\<clsid>" - I can then look at the key (for example) "InprocServer32" and find the server name/location.

Incidentally, there is some code to do this and more here[^]. This is great but I just thought there may be some macro or API call I'm missing which can do it without me having to explicitly look it up in the registry.

"The folly of man is that he dreams of what he can never achieve rather than dream of what he can."

"If you think education is expensive, try ignorance."

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