here lHelpID is the mapid of my text/edit box for which i want to open help.
The problem here is when I use F1 key to open help for two diffrent text box (say FirstName and latname text boxes) it open the help for one and not for other textbox. But in help file the help tags for both textboxes are set up and directed to same topic.
Can anyone please help if they have encountered similar problem?
I am new to c++ and I will use it in my thesis on image processing.
I wrote a piece of code to read a ppm image file. in order to read the magic number (the number indicating the type of the image file whether it is ppm, bmp, jpeg or etc. this magic number is in the header section of the image) i create a char pointer magicNumber:
char *magicNumber;<br />
magicNumber = new char;// my aim is to create a pointer just to copy the "P6", i tried using malloc, but it did not fix
and pass it into the function PPMreadHeader. My intent is to fill the pointer inside the function and write the magicnumber in the console outside the function.
i have an array in the PPMreadHeader fuinction in order to read the file line by line. I have a local char pointer "word":
char line;<br />
char * word;
when i read the magicnumber (it is "P6" for ppm files) i assign it to the local pointer word:
if i try to write the magic number in the function using the local pointer:
there is no problem, it writes p6 to the console. however, if i first copy the word into the magicnumber pointer that i create in the main function:
and then try to print out the pointer to the consolelike below:
then it writes:
which not i want. it writes the p6 which is what i want to write to the console, but it writes more than p6. within the function when i write the local pointer "word" it just writes the P6, nothing more. Could you please help me on this.
You may advise other alternatives to write the magic number on to the console but even you do this, i still want to learn what is wrong with my coding. i spent a lot of time on this and i could not fix it.
Can anybody explain in details how to expose a C# WinForms Control as ActiveX control. Either via hosting it in a MFC ActiveX control or by implementing it completely in C# (implementing all interfaces, registration/unregistration stuff, events).
Perhaps somebody has a template project for this problem where I just can drop in my Windows Forms Control and is willing to share it with me and the others (sounds like XMas, I know).
We have a large client application with lots of legacy code that implements an ActiveX container. So you can add e.g. GUI components by providing new ActiveX controls. Since we have almost year 2007 we want to develop new GUI components with Windows Forms instead of the existing MFC/OWL stuff (yes! OWL! ). We recently migrated to Visual Studio 2005 (.NET 2.0).
As far as I can see there are 2 main approaches: (Approach 1) Use of a MFC ActiveX control for hosting the Windows Forms control and use the new MFC 8.0 template classes CWinFormsDialog[^] or CWinFormsView[^] for adding the WinForms control to a CDialog/CView.
(Approach 2) Implement all necessary COM interfaces completely in C# and make them visible to COM and do the extra COM registration/unregistration stuff as explained here[^]. So the resulting component would be completely written in C# with no other languages involved. Furthermore we have about half a dozen COM interfaces for communication between the client and the ActiveX component. These interfaces must be implemented too. Sounds like very much more work than approach one.
So we decided to follow approach one - hosting a WinForms control within a MFC ActiveX control. What a pain until now!
(1) Created an "empty" MFC ActiveX control, with all of our COM interfaces, showing an empty CDialog. Works flawlessly when added to the client application or to the ActiveX Control Test Container.
(2) Enabled Common Language Runtime Support (/clr) for the project. After fixing some compiler warnings the project compiles fine to MSIL.
( #1) Here is already the first major problem: When the project is started after '/clr' is activated, Visual Studio 2005 locks up completely while loading the CLR DLLs (e.g. 'mscoree.dll', 'mscorwks.dll'). There is no error message or crash, but VS2005 hangs infinitely and the only thing to do is killing the 'devenv.exe' process. Why is this? But it's possible to start the application regularly! Only when started via VS2005 it hangs. The ActiveX still shows up correctly when the application is not launched via VS2005.
(3) Since I found no solution for this problem I sighed and added a CWinFormsControl member to the "empty" CDialog as described in the MSDN example here[^] (which works by the way perfectly when used in a stand alone dialog application). I tried two variants:
( #2) When the ActiveX is about to be displayed it crashes in 'CWinFormsControl<TManagedControl>::InternalCreateManagedControl' (<VS2005-install-path>\vc\atlmfc\include\afxwinforms.inl). Output window says: A first chance exception of type 'System.AccessViolationException' occurred in <MyActiveX>.OCX
I got this information by attaching to the application process with VS2005 when the application is already running.
I read several threads where members of the Visual Studio Team and MVP's are saying that MFC 7.1/8.0 are officially supported unmanaged hosts for Windows Forms controls, just like Internet Explorer. But it seems not to apply for MFC ActiveX controls!?
If they give you lined paper, write the other way!