I am working on an OPC HDA Client where I am creating a Conenction with OSI PI HDA Server via below code. But at the time of Advise to the Server I am getting an error with error code = 0x80040202. The OSI HDA server is located on remote machine which has full DCOM configuration. I searched out and found that this happens due to CONNECT_E_ADVISELIMIT or CONNECT_E_CANNOTCONNECT. Below is the my code of Connect(). Can anybody help me what else I have to do to fix the problem.
#pragma region Code Added For AsyncOperations
ATL::CComPtr<::IConnectionPointContainer> subscripCpcObj = GetAtlInterface<::IConnectionPointContainer>((this->RawObject));
HRESULT hr = subscripCpcObj->FindConnectionPoint(__uuidof(IOPCHDA_DataCallback), &eventObjPtr);
// Get the servers side of the connection.IntPtr cbPtr = Marshal::GetComInterfaceForObject(this, OpcHdaEventSink::typeid);
callbackPtr = reinterpret_cast<IOPCEventSink*>(cbPtr.ToPointer());
// Advise for the events.
hr = eventObjPtr->Advise(callbackPtr, &cookie);
//Hold a reference to the connection point for shutdown.
this->callbackCookie = cookie;
this->callbackConnectionPoint = GetDotNetInterface<::IConnectionPoint>(eventObjPtr);
if(this->callbackConnectionPoint == nullptr)
OutputDebugString(L"HdaServer:->callbackConnectionPoint is NULL!");
I have created the COM component in VC6.0 using ATL 3.0
I am using it in VB6.0
I have added the BSTR Event.
I want to pass the string with NULL character in between the string from VC to VB
e.g. I want to fire a event with string "ABC\0XYZ"
So I can get the complete string in VB as ABCXYZ
 - indicates box as unicode character.
But I am getting only "ABC" string.
Please tell me the way to pass the string with NULL character from vc to vb.
Note: Without seeing any of your code, I'm just guessing...
It's probably because when you create the BSTR, you let it count characters to determine its length, rather than telling it what the length actually is. Any string length function in C/C++ will see a NULL as the end of string.
So, create your BSTR like this, telling it what its length is:
BST b = SysAllocStringLen(L"ABC\0XYZ", 7);
Java, Basic, who cares - it's all a bunch of tree-hugging hippy cr*p
As I recall you won't be able to do as you want, either the ATL Event Wizard generated code sees the internal NULL and loses the rest (even with the BSTR length set) or VB will see a a NULL terminated string. I'm pretty sure You'll have do do more one way or the other. Maybe pass an array of characters?
The NULL character is your problem. Try replacing it with some other unique Unicode character which both parts of your application can recognise. Alternatively put the box character in your source string in the first place.
I am using namespace MSXML in my application to traverse and read XML file.But I have some confusion regarding MSXML is that this one is related to c++ DOM APIs na? And what its relation with COM?
And these both COM AND DOM are provoding different APIs?and then what is DCOM?
did you introduce new controls such as button to outlook UI for this purpose? or did you subscribed for Send/Receive event via connectionPoint? Explaining the procedure you have followed may help to get quick solutions..
I have introduced new toolbar using ATL.On selecting some mails and clicking on the button, mail details will be sent to a web service.The part of retrieving the mail details is working fine.On doing the export a few times, and then clicking on Send/Receive button, a message box "Could not complete the operation" appears.
As the message box does not appear on a single Export action, i could not find the scenario.
problem seems strange, but after googling the error msg, it is found that this error msg comes in several other scenarios like repeatedly creating New Appointment, New Tasks etc also. So can we conclude that repeatedly retrieving mail items conflicts with send/receive action.?
thanks for your time..
yes.. the error msg comes in several case in outlook.i am trying to find what causes the Send/Receive action to show the error msg.
what object of outlook gets changed, so the error occurs on the Send/Receive action??
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I have the following method to capture image from a window it works ok but today it save the same image to disk every times called. Please help me! I cannot understand what is the problem.
public void GetWindowPicture(IntPtr hWnd)
IntPtr hdcDest = default(IntPtr);
IntPtr hdcSrc = default(IntPtr);
RECT r = new RECT();
int w = 0;
int h = 0;
GetWindowRect(hWnd, ref r);
w = r.Right - r.Left;
h = r.Bottom - r.Top;
Bitmap bm = new Bitmap(w, h);
Graphics g = Graphics.FromImage(bm);