HRESULT and Borland C++ Builder - COM Discussion Boards

Shutter3-Jan-05 15:47

3-Jan-05 15:47

I'm working on a plugin system, however I do not want end users to be able to discover what interfaces/coclasses I have implimented in the plugin DLLs.

If I remove the type library from the DLL's resources, will the plugged-into app still function correctly as long as it knows the definitions of the plugins' interfaces at compile-time?

If the plugin DLL does NOT contain a type library in itself, will the app and plugin still function properly?

Re: Removing the type library from a DLL

FearlessBurner4-Jan-05 10:34

FearlessBurner

4-Jan-05 10:34

The type library in the resources is just included for convenience so that other programmers can view the COM interfaces etc. but does not directly affect the actual interfaces implemented. If you remove this information from the DLLs resource (comment out the lines in the .rc file), the actual interfaces will still function normally.

Re: Removing the type library from a DLL

Shutter4-Jan-05 11:39

Shutter

4-Jan-05 11:39

Thanks

Re: Removing the type library from a DLL

ThatsAlok4-Jan-05 17:25

ThatsAlok

4-Jan-05 17:25

I know this very stupid Question ,just want to know which line to comment out in RC File.

Thanks

"I Think this Will Help"
Alok Gupta
visit me at http://www.thisisalok.tk

Re: Removing the type library from a DLL

FearlessBurner5-Jan-05 6:20

FearlessBurner

5-Jan-05 6:20

Near the bottom of the .rc file, you will see a line like this:

1 TYPELIB "myproject.tlb"

If you comment out this line, then the type libary will not be included (assuming that APSTUDIO_INVOKED has not been defined).

If APSTUDIO_INVOKED has been defined, then you will need to comment out the TEXTINCLUDE section higher up in the .rc file which contain a similar TYPELIB line.

Re: Removing the type library from a DLL

ThatsAlok5-Jan-05 6:47

ThatsAlok

5-Jan-05 6:47

Thanks Sir!
I got it!!

Thanks Once Again

"I Think this Will Help"
Alok Gupta
visit me at http://www.thisisalok.tk

Help!! VB6 .ocx in VB.NET....

Sylan3-Jan-05 8:38

Sylan

3-Jan-05 8:38

Hi..

I have an .ocx that is made with VB6 and which contains an interface to it's functions and properties.

I have used the aximp tool to create a dll file which I reference in my project.

When I try to access some of it's functions or properties I get the errormsg.:

"An unhandled exception of type 'InvalidActiveXStateException' occurred in axinterop.itdcinterfacelib.dll"

But when i set a breakpoint in my code and expands the variabletree for the interfaceobject in the Locals window and then steps forward in the code, it works fine...!!

I guess it has something to do with initzialisation, but I can't find a solution to this... Sigh | :sigh:

Please help me...

HRESULT and Borland C++ Builder

Andrew Tomsen3-Jan-05 1:02

Andrew Tomsen

3-Jan-05 1:02

I am trying to write an Automation-Server with Borland C++ 6.0. The server has to run a model. The interface contains a method to actualize the state of the model. For this reason the method takes some values as parameters.
HRESULT actualize_model( [in] double value1, [in] double value2 );
There has no value to be to return. The only thing the client has to know is that the passed values has been sucessful processed. In other words the client must be sure that the method has been carried out.
The borland wizard that builds the com server encapsulates the method. The same if I write the client. I call Project->Import Type Library... and the wizard generates some code. All I can see is a Object which contains the following method without an HRESULT:
void actualize_model( double value1, double value2 );

Now my question: How is it possible for the client to recognise that the call has failed? I wonder why there is no exception thrown after a method call while the server is closed.

Andrew

Re: HRESULT and Borland C++ Builder

Jörgen Sigvardsson3-Jan-05 8:35

Jörgen Sigvardsson

3-Jan-05 8:35

I don't know how Borland's importing features work, but I do know that Visual C++ creates wrapper code which transforms:

HRESULT Method([in] long v, [out, retval] double* pResult)

into

double Method(long v) throw(_com_error)

. In other words, it creates code which looks kind of like this:

double WrappingMethod(long v) {
   double result;
   HRESULT hr = Method(v, &result);
   if(FAILED(hr)) throw _com_error(hr);
   return result;
}

Perhaps the Borland code generates the same kind of code?

In Visual C++, you can tell the compiler not to generate this wrapper code, so that you'll get pure untampered interface definitions. Are there any such options for Borland?

--
I got nasty habits. I take tea at three.
-- Mick Jagger

I blog too now[^]

How to pass ASP Checkbox values to ATLCOM Dll

Srihari_81852-Jan-05 22:30

Srihari_8185

2-Jan-05 22:30

Hello,
Any body can pls help me how to pass multiple checkbox values to a ATL COM Dll.am new to ASP.
Thanks.
R.Srihari

ofstream not working in unmanaged code

sprinkler30-Dec-04 14:11

sprinkler

30-Dec-04 14:11

Hello,
I have an unmananged COM object that at one time would send error messages to a text file that was created by using
ofstream outfile;
outfile.open("C:\\WhatHapped.txt");
but, I don't know why it stopped working.

The COM object is used in our asp.net program that is using c# code to grab the com functions.

Could there be something in web.config that isn't allowing the file being created in the COM object?

Thank you,
Bill

Execute javascript through c++

fe328-Dec-04 6:44

fe3

28-Dec-04 6:44

I need to invoke a script function programmatically through c++. I have the relevant html doc and there will be several script tags. I have the collection of tags and loop through them to find the script function. However, when I get to the script element that I know contains the function, the GetIDsOfNames method always returns "Unknown name."

CODE SAMPLE

CComBSTR bstrMember("SCRIPT");

pDoc3->getElementsByTagName(bstrMember, &pEltColl);

long len;
pEltColl->get_length(&len);
for(int i = 0; i < len; i++ )
{
CComPtr<idispatch> pEltDisp = NULL;

hr = pEltColl->item( CComVariant(i), CComVariant(i), &pEltDisp);

if(SUCCEEDED(hr))
{
IHTMLScriptElement* pElem = NULL;
hr = pEltDisp->QueryInterface( IID_IHTMLScriptElement, (void**)&pElem );

IDispatchPtr spDisp( pElem );

if(SUCCEEDED(hr))
{
OLECHAR FAR* bstrMember = L"MyFunction";
DISPID dispid = NULL;

**************Things go wrong here****************************

hr = spDisp->GetIDsOfNames(IID_NULL,&bstrMember,1,
LOCALE_SYSTEM_DEFAULT,&dispid);

if(SUCCEEDED(hr) && dispid )
{
DISPPARAMS dispparams;
memset(&dispparams, 0, sizeof dispparams);
EXCEPINFO excepInfo;
memset(&excepInfo, 0, sizeof excepInfo);
CComVariant vaResult;
UINT nArgErr = (UINT)-1;
//Call JavaScript function
hr = pEltDisp->Invoke(dispid,IID_NULL,0,
DISPATCH_METHOD,&dispparams, &vaResult,&excepInfo,&nArgErr);
}
}
}
}

Suggestions would be welcome

Creating class wrappers for ActiveX controls (mappointctrl.ocx)

BlackDice28-Dec-04 6:42

BlackDice

28-Dec-04 6:42

I tried using the type library for Microsoft Mappoint to generate classes I need to use the activex control on my dialog, but couldn't seem to see any way to make that work. Now I've tried generating classes from the .ocx file, and that seems to give me all the classes I need for what I'm trying to do. However, I have no idea how to actually display the control on my dialog. There's a CMappointCtrl class that was generated, and all I see in the member functions is CreateDispatch(), not a Create() since it's not derived from CWnd. Also, there's a bunch of other classes that came from the .ocx that I would like to use (like CRoute,CMap). How can I use these with the control? Any help is appreciated. thanks

My articles

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BlackDice

how can I reg the DLL for print Function(with code)

wangguangda27-Dec-04 17:16

wangguangda

27-Dec-04 17:16

no.1 I've disabled all the virus software ,fireware&Internet Assistant
no.2 I've try to import the related item into register and copied dll files to system directory

but the Activex Control can not work still, hot can... how can I do?

<object id="factory" viewastext="" style="display:none"
="" classid="clsid:1663ed61-23eb-11d2-b92f-008048fdd814" codebase="/scriptx/ScriptX.cab#Version=6,1,431,1">

EXE COM Servers and Apartments

Lim Bio Liong25-Dec-04 15:51

Lim Bio Liong

25-Dec-04 15:51

Hello All,

I have a question which I hope my esteemed peers here will be able to provide some comments :

1. After some time of researching, I found that a COM Object in a COM EXE Server cannot decide on its own Apartment Model (Apartment, Multithreaded, etc).

2. This is so despite indicating the model you want when creating an ATL COM object inside an EXE Server using the ATL Wizard.

3. The way to indicate the Apartment Model for your COM Object is to place your call to CoRegisterClassObject() on your COM Object Class Factory in a thread that has been initialized with CoInitializeEx(NULL, COINIT_MULTITHREADED) or CoInitializeEx(NULL, COINIT_APARTMENTTHREADED).

Any comments on this from anyone ?

Many Thanks, All,
Bio.

Re: EXE COM Servers and Apartments

Martin Koorts4-Jan-05 0:09

Martin Koorts

4-Jan-05 0:09

Hi Bio

Inspecting the CAtlExeModuleT class (from the ATL classes shipping with VC.net 2003), I notice the InitializeCom method, quoted below;

<snip>
static HRESULT InitializeCom() throw()
{

#if ((_WIN32_WINNT >= 0x0400 ) || defined(_WIN32_DCOM)) & defined(_ATL_FREE_THREADED)
return CoInitializeEx(NULL, COINIT_MULTITHREADED);
#else
return CoInitialize(NULL);
#endif
}
<snip>

which would lead me to believe that by setting _WIN32_WINNT, _WIN32_DCOM, and/or _ATL_FREE_THREADED to the desired values, you would be able to have the server enter the apartment of your choice.

HTH

Martin

Re: EXE COM Servers and Apartments

Lim Bio Liong6-Jan-05 20:49

Lim Bio Liong

6-Jan-05 20:49

Hello Martin,

Thanks very much for your advise, Martin. I was also observing the difference between a COM DLL Server and a COM EXE Server in terms of specifying the Apartment Model of objects.

DLL server objects indicate their individual Apartment Model in the registry. The ATL Wizard arranges for this. One advantage of using a DLL-based server is that you can specify two objects of different Apartment Models in the same server.

For Exe Server objects, I'm now wondering if it would be possible to specify two object classes with different Apartment Models. I think it may not be possible to do this using ATL. You would have to manually create threads to register the class factories. I'll do some experiments to confirm this.

Thanks again, Martin,
Bio.

ActiveX/COM on J#

Maverick23-Dec-04 12:54

Maverick

23-Dec-04 12:54

i Don't know if this the right thread to post.. but...

our company is planning to buy a third party ActiveX/COM component.

But we need to use it in Java Code... I was wondering if I could call the COM component using J#?

COM Controls

csharp623-Dec-04 7:22

csharp6

23-Dec-04 7:22

I am wanting to use COM controls in my management scripts written in VBS. Which controls are available to me and how can I use them.

Thanks in advance. Smile | :)

God answers knee mail.

Simple (hopefully) event question

__makaveli__21-Dec-04 23:54

__makaveli__

21-Dec-04 23:54

I am porting an app from VB to C++, it uses Crystal Reports and in the VB app an event is handled using the "Handles" operator, I now need to handle that event in C++.

I am #import'ing the CRAXDDRT20.dll and using the IApplicationPtr and IReportPtr objects to initialise and start a report export, the event fired is called "BeforeFormatPage" in VB, how would I go about handling it in C++? (This is the first time I have used COM in C++ BTW)

Re: Simple (hopefully) event question

ThatsAlok22-Dec-04 17:28

ThatsAlok

22-Dec-04 17:28

you can look here for your need-->

http://www.codeproject.com/com/TEventHandler.asp[^]

"I Think this Will Help"
Alok Gupta
visit me at http://www.thisisalok.tk

Re: Simple (hopefully) event question

__makaveli__6-Jan-05 5:19

__makaveli__

6-Jan-05 5:19

I have read that and played around with the example but I just don't get it.

I have found this code in the .tlh file for my object:

#pragma implementation_key(2)
inline HRESULT CRAXDDRT20::IReportEvent::BeforeFormatPage ( long PageNumber ) {
return _com_dispatch_method(this, 0x2, DISPATCH_METHOD, VT_EMPTY, NULL,
L"\x0003", PageNumber);
}

Does that give any clues as to what direction I should be heading in.

Sorry if this sounds really dumb, I feel really dumb, I can normally understand and make most things work but COM is really baffling me Frown | :-(

Cheers,
Dan.

Re: Simple (hopefully) event question

ThatsAlok6-Jan-05 6:36

ThatsAlok

6-Jan-05 6:36

Why are you reading .tlh file sir!,that the compiler generate for you when you import COM dll in your project.

i think you Event returning LONG as parameter

"I Think this Will Help"
Alok Gupta
visit me at http://www.thisisalok.tk

Re: Simple (hopefully) event question

__makaveli__6-Jan-05 7:23

__makaveli__

6-Jan-05 7:23

It was the .tli file, not .tlh, that was a typo but it was the only file I could find a reference to the event I was interested in and so thought it might provide a clue as to how to capture the event.

As for importing a COM dll into my project, I have never done that, would that possibly be a step towards capturing this event?

I am not using MFC or classes BTW, just plain C.

E_INVALIDARG with EnvDTE::Commands::AddNamedCommand

Franz Klein21-Dec-04 21:35

Franz Klein

21-Dec-04 21:35

I am always getting a return value of E_INVALIDARG when the function AddNamedCommand is called: Cry | :((

CComPtr<envdte::command> pCreatedCommand;

hr = pCommands->AddNamedCommand(m_pAddInInstance, CComBSTR(commandname), CComBSTR(commandtext), CComBSTR(tb_name), VARIANT_FALSE, IDB_LOGO, NULL, EnvDTE::vsCommandStatusSupported+EnvDTE::vsCommandStatusEnabled, &pCreatedCommand);

IDB_LOGO is a 16x16 Bitmap.

I am using Visual Studio .NET 2003 on Win XP SP2. I have looked at the documentation and at other examples but I can't find where I am going wrong. I have exactly the same code as everybody else, but theirs works fine.

Any ideas?

I am the handsome one in the crowd.

Use Ctrl+Left/Right to switch messages, Ctrl+Up/Down to switch threads, Ctrl+Shift+Left/Right to switch pages.