Re: VB6 - C# interop. Returning an arrays. MarshalAs? - COM Discussion Boards

pra84veen9-Jun-08 0:28

9-Jun-08 0:28

hi one and all,

iam having a problem with accessing serial port in my pc. i have developed an application which access the serial port in VC++ 6.0.After configuring the Serial port to 115200, iam able to send the data to the com port using WriteFile().But, iam unable to receive the data from the com port through ReadFile() operation and i have checked the error by using GetLastError() and it is given as 995(system error code).Even though i have restarted my system several times,iam unable to debug.

Please help me why this error is getting and how to fix this error?

Thanks in advance
Regards,
Praveen

Re: regarding System Error Code 995

CPallini9-Jun-08 0:51

CPallini

9-Jun-08 0:51

Could you post the relevant code?
BTW this forum is about Component Object Model technology [^], not about serial port communication.

If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler.
-- Alfonso the Wise, 13th Century King of Castile.

This is going on my arrogant assumptions. You may have a superb reason why I'm completely wrong.
-- Iain Clarke

Re: regarding System Error Code 995

Mike Dimmick10-Jun-08 2:56

Mike Dimmick

10-Jun-08 2:56

C:\>net helpmsg 995
 
The I/O operation has been aborted because of either a thread exit
or an application request.

Most likely it simply timed out. See SetCommTimeouts for information.

DoEvents: Generating unexpected recursion since 1991

Re: regarding System Error Code 995

buntyrolln12-Jun-08 2:43

buntyrolln

12-Jun-08 2:43

You can go through the link given below.
Go through the details of each and every Read and Write functions.
http://msdn.microsoft.com/en-us/library/ms810467.aspx[^]

If you do not get the solution your queries are always welcome.

buntyrolln

OLE Control Draw & Update Problem

DavidRipple7-Jun-08 20:16

DavidRipple

7-Jun-08 20:16

I create a ImageOle project to encapsulate Image to OLE object so as to display JPG,GIF,TGA... image in CRichEditCtrl. When dispaying animated GIFs,I coded in OnTimer:

IAdviseSink* pAdviseSink=NULL;
if(S_OK==GetAdvise(NULL,NULL,&pAdviseSink))
{
pAdviseSink->OnViewChange(DVASPECT_CONTENT,-1);
}

TCHAR buffer[100];
_stprintf(buffer,_T("OnTimer:Frame :%d,Total:%d\n"),
m_pImageObj->GetFrame(),
m_pImageObj->GetNumFrames());
OutputDebugString(buffer);

I traced the debug string(by above ::OutputDebugString),the frame of Gif switch as expectedOnTimer,and meanwhile by calling OnViewChange ,I get the control container call
HRESULT CImageAnimator::OnDraw(ATL_DRAWINFO& di),the draw operation is also okay,However,for some unknown reason, after OnDraw,My Ole Control is not visually updated in CRichEditCtrl,it is always stayed in Frame 0 although I have updated the frame index and called the container to update the view of my control.

I think the pAdviseSink->OnViewChange and OnDraw mechanism doesn't work as I expected, it seems that the OnDraw operation doesn't work.

Which API is used for changing the video settings.

balaji_vbr6-Jun-08 19:54

balaji_vbr

6-Jun-08 19:54

Dear sir,

1.we are developing one video-email project. in that we are using "CODEC" com object for video recording & displaying.
2.Coder records the viddeo. Decoder Disply the video.
3.We used Windows Media Encoder 9 series SDK.
4.we used WME-Interfaces(we used WMEncoder & IWMensouce Interfaces,... ) for recordig video,displying video etc....
5.NOW I WANT TO CHANGE VIDEO SETTINGS LIKE: "Brightness" & "color" & "sharpness" of the video
6.to change the video settings i want one API. i dont knoew how to use the the API call for changing the video settings
7.i have UI (User Interface) with 3 SLIDER BARS(track bars) to increase or decrease the brightness,color,sharpness.
8.i have 3 buttons(APPLY,CANCEL,OK) in that UI to change the settings.
9.And i have a DEFAULT button to set the brightness,color,sharpness to default.
9. while drag the SLIDER BAR forward/backward the brightness,color will increase/decrease respectively.
10.when i click on apply the settings will apply to the video.

this is my requirement please help me to complete my project.its urgent.

Regards,
Balaji.

VB6 - C# interop. Returning an arrays. MarshalAs?

Simon P Stevens6-Jun-08 0:07

Simon P Stevens

6-Jun-08 0:07

Hi,

I'm writing a C# class that will be used by a VB6 application. The class has a method that needs to return an array of custom objects.

Initially I just couldn't get this to work. I got a "type mismatch" error every time the call was made in VB.

then I found this[^] page which suggested tagging the interface with [return: MarshalAs(UnmanagedType.AsAny)]. This got it working. Big Grin | :-D

My question is why does this work?

As I understand it, MarshalAs(UnmanagedType.AsAny) dynamically detects the type and marshals as the correct type, but I know what type it is, why wouldn't VB accept it as an array of MyClass. MyClass is fully com visible and VB is happy to use it fine in several other areas, it just doesn't like the MyClass[] when returned from a c# method.

I've programmed C# & VB6 separately loads before, but this is my first attempt at any interop.

Can anyone explain or point me at a good resource?

Cheers

[Sorry if this is the wrong place to ask. I know it's VB6 - C#, but I thought the problem is more related to the COM interop factor. If anyone thinks otherwise, shout and I'll move it]

Simon

Re: VB6 - C# interop. Returning an arrays. MarshalAs?

Baltoro12-Jun-08 6:51

Baltoro

12-Jun-08 6:51

You might read up on: Interop Marshaling[^].
This is a very confusing subject initially, because the NET Framework tries to bridge the syntactic and logical differences between programming languages and their compiled binaries.
This MSDN page details Corresponding COM and NET Framework Types[^]
You want to understand the Default Marshaling Behavior[^] when using the MarshalAs attribute, because there are restrictions to the NET Framework methods based on equivalence of data types defined in both unmanaged Visual Basic and managed C# (I'm assuming the Visual Basic component is COM).
Also informative are: Marshaling Data with COM Interop[^], and, Assembly to Type Library Conversion Summary[^].
Essentially, when passing an array of objects between NET and COM, the conversion of the data structure is ambiguous, and so are not compatible to their respective runtime libraries. This is explained better over at MSDN: Blittable and Non-Blittable Types[^], and, Default Marshaling for Arrays[^].

Re: VB6 - C# interop. Returning an arrays. MarshalAs?

Simon P Stevens12-Jun-08 10:57

Simon P Stevens

12-Jun-08 10:57

Wow, Thanks for all that Smile | :)

. I've got some serious bedtime reading there. I'll be an expert by Monday morning.

Simon

DirectShow video capture and play back synchronisation problem

ak$12345-Jun-08 22:04

ak$1234

5-Jun-08 22:04

I am new to DirectShow and am developing an application to capture video using a video capture device. I am using DirectShow to control the device to capture avi files. I can successfully capture avi, but when i play back the avi file i find that the play back time is longer than the time i captured for. For example, if i capture video from a monitor which is playing a clock and i record for 20 seconds, the avi file is of duration 24 seconds. During playback, the clock correctly ticks 20 times but the playback takes 24 seconds. In effect, time has slowed down!!!

I have tried this both in GraphEdit and programattically with the same results.

I am using an Epiphan DVI2USB Solo device for the capture and an ffdshow vide encoder.

The graphEdit graph is:

DVI2USB Solo --->> ffdshow video encoder --->> AVI MUX --->> *.avi

On the AVI MUX I have to clear the Compatibility Index, otherwise only one image is captured the device and displayed during playback.

From a code point of view I am enumerating the capture devices and the codec and selecting the one i want. I construct an ICaptureGraphBuilder2 to construct the graph and attach it to a FilterGraph. After calling SetOuputFilename and RenderStream on the ICaptureGraphBuilder object i use IMediaControl from the FilterGraph to run and stop the graph.

Has anybody encountered this problem before? Are there any settings i need to configure? Any help/suggestions would be much appreciated. I have searched Google, MDSN and other forums without finding anyhthing that would help.

Many thanks.
AK

Re: DirectShow video capture and play back synchronisation problem

stuart151-Sep-08 0:00

stuart15

1-Sep-08 0:00

Maybe your PC can not playback at the same framerate that you recorded your avi file at?

Launching multiple IE [modified]

Nirav Doshi5-Jun-08 8:19

Nirav Doshi

5-Jun-08 8:19

Hi,

For a particular requirement, currently my testing team has isolated multiple copes of IE5.5 (in seperate folders with *all* the required DLLs within that folder). They launch multiple copies (sometimes upto 100) of the IE5.5 for their testing to allow individual sessions.

I'm trying to automate this, and for the same (with my very limited knowledge of COM) am trying to do the following. Please help me here to tell me if I am on the right track?:

1. I have a dialog based MFC app can launch each of the 100 different copies of IE 5.5 from their individual 100 folders using CreateProcess()

2. In the app I'm also doing (only once - I suppose this is primarily required for generating the TLH/TLI files):

#import "C:\IE Copies\IE551-1\SHDOCVW.DLL"

Doubt: As each of the 100 folders containing the IE5.5 have their own SHDOCVW.DLL, do I need to import them individually, or should this suffice?

3. After the IEs are running, next I need to "reach" their individual IWebBrowser2 interfaces (exposed by their SHDOCVW.DLL) so that I can invoke the navigation methods to automate visiting sites, logging in, etc.

Please note - The IEs are *not* registered with the system (obviously) - and so the usual methods may not work.

Doubt: Is there some way I can use CoCreateInstance() such that I can launch each of the IE5 copies, even though they're not registered on the system.

Sorry - if this sounds crude/crazy... I'd really appreciate if you can suggest a solution to this -- or even a more appropriate/elegant method to get this going.

Thanks a lot in advance, for your time & efforts.

Rgds,

nd

modified on Thursday, June 5, 2008 2:31 PM

Re: Launching multiple IE

Nirav Doshi5-Jun-08 10:11

Nirav Doshi

5-Jun-08 10:11

I think I can use the concept from: How to get IHTMLDocument2 from a HWND[^]

Since the method needs a HWND, I need to write a PIDtoHWND() after I do the CreateProcess() which will get me only the PID.

Phew... I hope this works! Yet to test it.

Thanks,

nd

Re: Launching multiple IE [modified]

Nirav Doshi12-Jun-08 18:04

Nirav Doshi

12-Jun-08 18:04

Stuck up once again! Frown | :(

I've used the code & concept as given at: How to get IHTMLDocument2 from a HWND[^]

With that, though I have a valid CComPtr<IHTMLDocument2> spHTMLDoc2, (valid because the spHTMLDoc2->put_bgColor(CComVariant("blue")) works fine) the get_parentWindow() doesn't work and gets a 0x00000000 in the spHTMLWindow2.

Is there something wrong with the way I'm doing this?

spHTMLDoc2->put_bgColor(CComVariant("blue"));

CComPtr<IHTMLWindow2> spHTMLWindow2;
hr = spHTMLDoc2->get_parentWindow(&spHTMLWindow2);

Thanks!

_{* Blood donation is the most superior form of donation, it can save lives. Celebrate special occasions, like your birthdays, by donating blood. *}

modified on Saturday, June 14, 2008 2:16 AM

Re: Launching multiple IE

Nirav Doshi14-Jun-08 0:10

Nirav Doshi

14-Jun-08 0:10

Finally, a good friend (Nanda) was able to help with this, and got the code below WORKING! This is how to get IWebBrowser2 from IHTMLDocument2.

Pasting code below for anyone who may need this. I had a very tough week wrestling with this, don't want anyone else to go through the same. Smile | :)

CComQIPtr<IOleObject>  spOleObject;			// IOleObject
CComQIPtr<IOleClientSite> spOleClientSite;		// IOleClientSite
CComQIPtr<IServiceProvider> spServiceProvider;		// IServiceProvider
...
...  // Code here as per <a href="http://support.microsoft.com/kb/q249232/">How to get IHTMLDocument2 from a HWND</a>[<a href="http://support.microsoft.com/kb/q249232/" target="_blank" title="New Window">^</a>]
...
HRESULT hRes = spHTMLDoc2->QueryInterface(IID_IOleObject, reinterpret_cast<void **>(&spOleObject));
if (SUCCEEDED(hRes))
{
	hRes = spOleObject->GetClientSite(&spOleClientSite);
	if(SUCCEEDED(hRes))
	{
		hRes = spOleClientSite->QueryInterface(IID_IServiceProvider, reinterpret_cast<void **>(&spServiceProvider));
		if(SUCCEEDED(hRes))
		{
			hRes = spServiceProvider->QueryService(SID_SWebBrowserApp,IID_IWebBrowser2, reinterpret_cast<void **>(&spWebBrowser));
		}
		if(SUCCEEDED(hRes))
		{
			BSTR oURL;
			oURL = SysAllocString(L"http://www.google.com");
			VARIANT var;
			var.vt = VT_EMPTY;

			spWebBrowser->Navigate((BSTR)oURL, &var, &var, &var, &var);
			SysFreeString(oURL);
		}
	}
}

Thanks a ton Nanda! Cool | :cool:

_{* Blood donation is the superior'est form of donation, it can save lives. Celebrate special occasions, like your birthdays, by donating blood. *}

Re: Launching multiple IE

Michael Dunn12-Jun-08 14:45

Michael Dunn

12-Jun-08 14:45

#import just creates the TLH/TLI wrappers as you said. Since all the IEs are the same version, they will support the same COM interfaces, so just one #import will be enough.

--Mike--
Visual C++ MVP Cool | :cool:

LINKS~! PimpFish | CP SearchBar v3.0 | C++ Forum FAQ

"That's what's great about doing user interface work. No matter what you do, people will say that what you did was idiotic." -- Raymond Chen

Re: Launching multiple IE

Nirav Doshi13-Jun-08 8:19

Nirav Doshi

13-Jun-08 8:19

Mike, thanks for the confirmation! Smile | :)

I'm still stuck up in a problem, posted above. Any ideas there? D'Oh! | :doh:

_{* Blood donation is the superior'est form of donation, it can save lives. Celebrate special occasions, like your birthdays, by donating blood. *}

Re: Launching multiple IE

Jörgen Sigvardsson13-Jun-08 10:49

Jörgen Sigvardsson

13-Jun-08 10:49

Why do you need several processes? Can't you just instantiate one IE, and then automate it to open 100 new windows?

--
Kein Mitleid Für Die Mehrheit

Re: Launching multiple IE

Nirav Doshi13-Jun-08 20:14

Nirav Doshi

13-Jun-08 20:14

The reason for several copies of IE is purely for the visiting site's session management.

New Windows don't allow a new session as well as multiple copies of the same IEXPLORE binary (different process). Hence the need to make multiple self-sustained copies of IE.

Thanks!

_{* Blood donation is the superior'est form of donation, it can save lives. Celebrate special occasions, like your birthdays, by donating blood. *}

Re: Launching multiple IE

Jörgen Sigvardsson13-Jun-08 22:14

Jörgen Sigvardsson

13-Jun-08 22:14

Oh, I see.. tricky. Perhaps it would be easier to create 100 user accounts, and run each instance for each user? Might be trickier in some other respects. (Just throwing out some random ideas here that might be of some use Smile | :)

)

--
Kein Mitleid Für Die Mehrheit

Re: Launching multiple IE

Nirav Doshi14-Jun-08 2:06

Nirav Doshi

14-Jun-08 2:06

Thanks! Yes, that's what is to be done. 100 browsers, running 100 user accounts simultaneously, automated.

Smile | :)

_{* Blood donation is the superior'est form of donation, it can save lives. Celebrate special occasions, like your birthdays, by donating blood. *}

Detect Network Adapters in Borland C++ Builder

Nekt Chrono4-Jun-08 21:54

Nekt Chrono

4-Jun-08 21:54

Hi all,

Does anyone know how I can initialize a VMI interface for Network adapters in Borland C++ 2006.
The class Win32_NetworkAdapter is not recognized by C++ Builder.

Generally is there any other means to detect and control (enable/disable) WiFi and Ethernet network adapters?

Thanks,

Nektarios

Excel WorkbookBeforeClose event Document Proof

HarishKumarS4-Jun-08 4:37

HarishKumarS

4-Jun-08 4:37

Hi All,

I need a documentation proof for the following observation i have made(presuming my observations are correct Smile | :)

)

I have written a addin for Microsoft Excel.
This addin handles the CLOSE event from the Excel.
But now , I have a Macro in an Excel sheet which is also listening for the close event.(the macro is as below)

Private Sub Workbook_BeforeClose(Cancel As Boolean)
If MsgBox("Confirm exit", vbYesNo) = vbNo Then
Cancel = True
End If
End Sub

And in the Addin , i am using the Cancel parameter as below.

OnWorkbookBeforeClose(IDispatch* pWorkbook, VARIANT_BOOL* pbCancel)
{

//So here pbCancel value is depending on what is clicked in that message box --
// As it is seen Message box has two buttons "Yes" and "No"
// If "No" button is clicked , the Cancel parameter value we get is "True"
// If "Yes" button is clicked, the addin does what is intend it to do.(i:e it closes the Excel)
}

As it is understood
This macro pops up a message box and can alter the "cancel" depending on what is clicked.
And in the Addin,
what i get now is the edited value of the "Cancel" parameter if "NO" button is clicked.

So, what i am assuming is, THE EVENT FIRST GOES TO THE MACRO AND ONLY THEN COMES TO MY ADDIN.

So, is my assumption Correct, if so , can i have some Documentation proof for the same(i:e - The control goes to the macro first and then will be sent to the Addin's (if any))

So, has any one come across the same situation.
It would be of great help if you reply me on this.

Thanks in Advance.
Harish

pass a parameter to a com+ application

Ayman Mashal4-Jun-08 0:19

Ayman Mashal

4-Jun-08 0:19

Hi ,

i have a vb com component dll , can i pass a parameter to this dll from the windows component services ?

i need that coz the dll connect to a database so i want to send the database from outside and not be
hard coded.

thanks

COM and Inteface/Implementation Polymorphism

kimutley3-Jun-08 10:02

kimutley

3-Jun-08 10:02

Hi all.

This is my 1st post to the Code Project so please excuse me if I step on some toes.

My question relates to polymorphism (I'm using VS 8.0 with ATL/COM). Assume the following (off the top of my head). What I want to do is to have a ITestOne interface with CTestOne implemented and a ITestTwo interface with CTestTwo implemented. I want to use ITestTwo to access ITestTwo interface implementations and to access ITestOne Interface implementations. I will have other classes derived from ITestTwo (e.g., ITestThree, ITestFour) and CTestThree derived from CTestTwo, etc.

Any suggestions???

TIA,

Kim

[
object,
uuid(F799607A-47E7-4582-B056-9FD4F5381BA5),
helpstring("ITestOne Interface"),
pointer_default(unique)
]
interface ITestOne : IUnknown{
};
[
object,
uuid(9AE009F8-99D9-4C4A-B0BC-9A34EEFCF78B),
helpstring("ITestTwo Interface"),
pointer_default(unique)
]
interface ITestTwo : IUnknown{
};
[
uuid(B7AB057E-F270-4019-966F-52E9994F82C2),
version(1.0),
helpstring("COMTest 1.0 Type Library")
]
library COMTestLib
{
importlib("stdole2.tlb");
[
uuid(F019A63E-D8ED-463B-AB5F-996A9231E448),
helpstring("TestOne Class")
]
coclass TestOne
{
[default] interface ITestOne;
};
[
uuid(31E6DA9C-DE0D-4B69-A259-1D39E136D31F),
helpstring("TestTwo Class")
]
coclass TestTwo
{
[default] interface ITestTwo;
};
};

Now I want to _really_ derive ITestTwo from ITestOne so both interfaces will be available in ITestTwo. To do this I change the following:

From: interface ITestTwo : IUnknown {};
To: interface ITestTwo : ITestOne

So far so good???... If so I then should be able to do the following (I only added the TestOneInterface() function to existing code generated by VS):

/**** CTestTwo Declarations ****/

class ATL_NO_VTABLE CTestOne : public CTestTwo
public CComObjectRootEx<ccomsinglethreadmodel>,
public CComCoClass<ctestone, clsid_testone="">,
public ISupportErrorInfo,
public ITestOne
{
public:
CTestOne()
{
}

DECLARE_REGISTRY_RESOURCEID(IDR_TESTONE)

BEGIN_COM_MAP(CTestOne)
COM_INTERFACE_ENTRY(ITestOne)
COM_INTERFACE_ENTRY(ISupportErrorInfo)
END_COM_MAP()

// ISupportsErrorInfo
STDMETHOD(InterfaceSupportsErrorInfo)(REFIID riid);

DECLARE_PROTECT_FINAL_CONSTRUCT()

HRESULT FinalConstruct()
{
return S_OK;
}

void FinalRelease()
{
}

public:

/**** CTestOne Implementations ****/
STDMETHOD(TestOneInterface)( void ) { }

};

OBJECT_ENTRY_AUTO(__uuidof(TestOne), CTestOne)

/**** CTestTwo Declarations ****/

class ATL_NO_VTABLE CTestTwo :
public CComObjectRootEx<CComSingleThreadModel>,
public CComCoClass<CTestTwo, &CLSID_TestTwo>,
public ITestTwo
{
public:
CTestTwo()
{
}

DECLARE_REGISTRY_RESOURCEID(IDR_TESTTWO)

BEGIN_COM_MAP(CTestTwo)
COM_INTERFACE_ENTRY(ITestTwo)
END_COM_MAP()

DECLARE_PROTECT_FINAL_CONSTRUCT()

HRESULT FinalConstruct()
{
return S_OK;
}

void FinalRelease()
{
}

public:

/**** CTestTwo Implementations ****/
STDMETHOD(TestTwoInterface)( void ) { }

};

OBJECT_ENTRY_AUTO(__uuidof(TestTwo), CTestTwo)

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