Re: Detecting the apartment - COM Discussion Boards

Re: How to keep a C++ com dll in memory?

Anonymously10-Apr-03 4:59

10-Apr-03 4:59

Thanks for the help. I don't want to make my com dll a service right now. I tried to return S_FALSE in DllCanUnloadNow and also called CAtlModule::Lock without calling Unlock. Doesn't seem to work.

I remember when building a com dll in VB6, you can specify a project setting called "retained in memory" which will do exactly what I want. Is there an equivalent of this feature in VC++?

Re: How to keep a C++ com dll in memory?

pba_13-Apr-03 7:17

pba_

13-Apr-03 7:17

Returning S_FALSE from DllCanUnloadNow should leave the dll loaded. I don't know VB, so I cannot tell exactly what that property does, but I suppose it will do the same thing ( return false from can unload now). Did you check if it's the same process ? ( maybe the process will exit, so normally all the dlls will be unloaded).

Client with flexible server name.

MauriceMG9-Apr-03 22:40

MauriceMG

9-Apr-03 22:40

I am new in COM programming so I have a question that is maybe very simple for you, but I do not know the answer.

My client and server applications are running on two different PC's, so I have a remote connection. I want to implement the client in such a way that the user can change the name of the PC where the server is running. I want this to be flexible for future changes if the server has to be installed on another PC.

Can someone explain me how to solve this? Do you have an URL where I can find an example with the solution for my problem.

Thanks.

MauriceMG

Re: Client with flexible server name.

pba_10-Apr-03 4:17

pba_

10-Apr-03 4:17

See the answer to "DCOM & Dual Lan" below [^]

Re: Client with flexible server name.

MauriceMG10-Apr-03 20:04

MauriceMG

10-Apr-03 20:04

My problem is solved now.

Thanks for your reaction.

MauriceMH

Detecting the apartment

Dave Bryant9-Apr-03 9:54

Dave Bryant

9-Apr-03 9:54

Does anyone know if there is a function I can call to determine if I an inside a STA or a MTA (apart from calling CoInitializeEx and checking for RPC_E_CHANGED_MODE).

Dave
http://www.cloudsofheaven.org

Re: Detecting the apartment

Vi29-Apr-03 23:14

Vi2

9-Apr-03 23:14

Looking for "DebugCoQueryApartmentID" word in MSDN's Bugslayer 1998[^].

With best wishes,
Vita

Re: Detecting the apartment

Dave Bryant10-Apr-03 9:51

Dave Bryant

10-Apr-03 9:51

Thanks

Dave
http://www.cloudsofheaven.org

Passing safearray of UDTs

bharanidharan9-Apr-03 9:32

bharanidharan

9-Apr-03 9:32

HI all,
I need to pass safearray of user defined data type( my structure ConInfoStruct) from the COM server dll to MFC client. I declared my structure in IDL file like this:

typedef [uuid(F5C2F02A-09D3-4fca-B5A9-5413009F6365)] struct tagConInfoStruct
{
ULONG m_ipAddress;
USHORT m_appType;
ULONG m_appID;
}ConInfoStruct;

when i build this code, MIDL doesnt generate GUID for the above structure. So Retrieving IRecordInfo pointer using UUID_ConInfoStruct from the client failed as UUID_ConInfoStruct is an undeclared identifier. Has anyone faced this problem before. Please let me know a solution for this problem.

thanks
bharani

Re: Passing safearray of UDTs

Vi29-Apr-03 22:47

Vi2

9-Apr-03 22:47

Remove the "tag" part from "tagConInfoStruct"! Also you should use OLE Automation types if you want use this structure in OLE client. Both ULONG and USHORT are incompatible with OLE. Use signed long and short types.

typedef [uuid(F5C2F02A-09D3-4fca-B5A9-5413009F6365)]
struct ConInfoStruct
{
  LONG m_ipAddress;
  SHORT m_appType;
  LONG m_appID;
}ConInfoStruct;

With best wishes,
Vita

COM messages

_Magnus_8-Apr-03 23:12

_Magnus_

8-Apr-03 23:12

Anyone knows what message ids com use for marshaling calls??

/Magnus

- I don't necessarily agree with everything I say

Passing SafeArray in Automation?

mandelbrot8-Apr-03 19:36

mandelbrot

8-Apr-03 19:36

In a MS Word automating program, I want to get a ShapeRange from a Shapes object, which need a SafeArray parameter. I wrote the following code:
------------------------------------------
COleSafeArray sa;
DWORD bounds=1;
sa.Create(VT_VARIANT,1,&bounds);
COleVariant v_ind((long)1,VT_I4);
long ind=0;
sa.PutElement(&ind,&v_ind);
//sa.Detach();

CShapes shapes(doc.GetShapes());
CShapeRange sr(shapes.Range(sa));
-------------------------------------------
It just throws an exception saying that the parameter has an invalid value. If I Detach the array before passing it to the Range method, the array becomes empty. Another exception is thrown out saying that out of bound.

Anyone can tell me how can I get it right?
Thx

Re: Passing SafeArray in Automation?

geo_m8-Apr-03 21:49

geo_m

8-Apr-03 21:49

Don't know about Word automation, but maybe it expect different type of SAFEARRAY - now you are passing to him an array of VARIANTs of type VT_I4, maybe he want's to accept only array of VT_I4 directly.
Or another possibility is, when I did something small with Word, he expected some number, but because it was optional, it had to be stored in VARIANT, so I feed him with VARIANT with VT_I4, but it failed with 'Bad parameter'. After playing a bit I found, that the beest expect to be filled with type set to VT_I2 and suddenly everything worked...

Hope this helps.

Re: Passing SafeArray in Automation?

Jon Taylor8-Apr-03 22:39

Jon Taylor

8-Apr-03 22:39

Have I understood this correctly, you want to receive a SafeArray from your call to shapes.Range ()? And this SafeArray will be populated with ULONGS?

Have a look at Chris Sells' SAFEARRAY Wrapper class:

http://www.sellsbrothers.com/tools/comvector.h

You should use it like this, where Size is the number of elements you are expecting back:

<br />
CComVector<ULONG> v (Size);<br />
CComVectorData<ULONG> rg (v);<br />
SAFEARRAY* sa = 0;<br />
v.DetachTo (&sa);<br />
<br />
CShapes shapes(doc.GetShapes());<br />
CShapeRange sr(shapes.Range(sa));<br />
<br />
// Access the data passed back<br />
for (int i = 0; i < rg.Length (); i++)<br />
{<br />
   DWORD Value = rg[i];<br />
}<br />

Hope this helps
Jon Smile | :)

Execute mode detection in EXE COM

Ryszard Krakowiak4-Apr-03 18:51

Ryszard Krakowiak

4-Apr-03 18:51

Hi
How to detect, if EXE COM is running form other application via COM call?

I 'd like to disable running executable COM as standalone application.

Thx 4 hlp

Re: Execute mode detection in EXE COM

Stephane Rodriguez.4-Apr-03 18:58

Stephane Rodriguez.

4-Apr-03 18:58

Running COM objects are registered in the ROT (Running Object Table). To get the ROT, just use the GetRunningObjectTable(...) WIN32 API function.

Re: Execute mode detection in EXE COM

J. Dunlap4-Apr-03 19:54

J. Dunlap

4-Apr-03 19:54

What language are you using? If VB6 then:
>The App.StartMode property will tell you whether you are running in standalone mode
>You can disable stand-alone execution by setting the start mode option to "ActiveX Component" in the Component tab of the Project Properties.
>VB objects are not registered in the running object table unless you register them there.

Re: Execute mode detection in EXE COM

Ryszard Krakowiak4-Apr-03 20:08

Ryszard Krakowiak

4-Apr-03 20:08

I use C/C++ in the executable COM and in the client.

Re: Execute mode detection in EXE COM

Vi26-Apr-03 20:42

Vi2

6-Apr-03 20:42

If EXE server starts by COM system, his command line contains the "Embedding" keyword.

OTOH, you can specify the necessary keyword(s) in .rgs file under "LocalServer32" key. E.g.

LocalServer32 = s '%MODULE% -Automation'

With best wishes,
Vita

ATL 7.0 Passing SafeArrays

Nicholas Cardi4-Apr-03 5:06

Nicholas Cardi

4-Apr-03 5:06

I want to pass a SafeArray to a VB Client but I can't seem to get the right syntax for the IDL.
Can someone please help me.

Forever Developing

Re: ATL 7.0 Passing SafeArrays

J. Dunlap4-Apr-03 6:47

J. Dunlap

4-Apr-03 6:47

[attributes] LPSAFEARRAY *varname

Re: ATL 7.0 Passing SafeArrays

Nicholas Cardi4-Apr-03 7:33

Nicholas Cardi

4-Apr-03 7:33

I should have been more clear.

I want to pass the SafeArray pointer out to VB 6 in ATL 3.0.
I used to be able to do this with the following code.

foo(SAFEARRAY(long) *psa);

However the same thing in ATL 7.0 won't compile

NOTE: I am using an emedded idl VS.NET

//Actual code

#define _ATL_ATTRIBUTES 1
#include "stdafx.h"
#include "resource.h"
#include "atlbase.h"
#include "atlcom.h"
#include "oleauto.h"
#include "atlsafe.h"
#include "oaidl.h"

// The module attribute causes DllMain, DllRegisterServer and DllUnregisterServer to be automatically implemented for you
[ module(dll,name="ATL7TEST")];

[object, dual, uuid(4D9BCA91-2F02-4cee-A589-2CC4D9821156)]
__interface IATL7TEST
{

HRESULT TestRaiseEvent();

};

[object,uuid("8D0F6D5E-DDC3-4371-BB08-49864F5DE356")]
__interface _IATL7EVENTS
{
HRESULT MyFirstEvent(SAFEARRAY(long*) *varname );

};

[coclass, uuid(EBAA6CB2-ED31-4e08-8DF8-068B2978C3F7),event_source(com)]
class TESTING :
public IATL7TEST
{
public:

__event __interface _IATL7EVENTS;
HRESULT TestRaiseEvent()
{
CComSafeArray<long> Test;
SAFEARRAY *psa;
SAFEARRAYBOUND rgsabound[1];
rgsabound[0].lLbound = 0;
rgsabound[0].cElements = 10;
psa = SafeArrayCreate(VT_INT, 1, rgsabound);
long test;
test = 1234;
LPSAFEARRAY lpsa;
lpsa = psa;

__raise MyFirstEvent(psa);
return S_OK;
}

};

//compilation errors
//v:\ATL7TEST\ATL7TEST.cpp(33): error C2061: syntax error : identifier 'tagSAFEARRAY'
//v:\ATL7TEST\ATL7TEST.cpp(33): error C2059: syntax error : ')'
//v:\ATL7TEST\ATL7TEST.cpp(33): error C2143: syntax error : missing ')' before ';'

Forever Developing

MFC->COM & JNI

GWENJi4-Apr-03 4:21

GWENJi

4-Apr-03 4:21

I am developing a COM dll that includes 3rd party dll in MFC 6.0. This 3rd party DLL reaches back into a java layer within itself via JNI(Java Native Interface). At my project level, I am getting
the following compile-time link time errors:

error LNK2001: unresolved external symbol "__declspec(dllimport) ?$S494@?1??IteratorClass@?$Iterator@VObservable@immaccs@@@util@@CAPAV_jclass@@XZ@4EA" (__imp_?$S494@?1??IteratorClass@?$Iterator@VObservable@immaccs@@@util@
@CAPAV_jclass@@XZ@4EA)

What is interesting is if I put the 3rd party stuff into a regular MFC exectuable project, the compile works fine. Projects are being compiled in release mode. Are there any known problems associated with a COM dll linking in another dll that has jni signatures in it?
Thank you for your time!

Plug n Play

Prabhakar3-Apr-03 11:27

Prabhakar

3-Apr-03 11:27

How do I connect to the interface of a component, without importing the type library (dont want to include header either) ? Is there anyway I can get the information from the registry, given the fact that I know the prototypes for the methods present in that interface ?

Basically, I want to access a new component without changing my client app. (Again, the new component's interface methods are known).

Thanks

<marquee>. . . _Humans^do_it^better. . .

Can I add a menu option to Internet Explorer?

rdautel3-Apr-03 7:41

rdautel

3-Apr-03 7:41

Hello,

I'm an experienced programmer, but new to COM. I'd like to add a new option to the 'right-click' menu in internet explorer so rather than performing a 'save as' command I can send GIFs and JPEGs directly to an art program I've written. Is this possible? It seems possible, I just can't find the info I need.

thanks.

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