C / C++ / MFC Discussion Boards

Re: is such exception handling approach good?

Matthew Faithfull21-Dec-07 2:05

21-Dec-07 2:05

Yes, that's as safe as you make Class1 and Class2 except in one instance, a stack overflow. In all other cases I know of, provided you have an exception handler somewhere up the stack then the Unwind function will be called in the runtime which uses a bit of compiler magic to ensure that the destructors for inst1 and inst2 are called. In the case of a stack overflow exception you're pretty much dead in the water. There is the _resetstkoflw() runtime function but it won't prevent anything allocated on the heap in your Class1 and Class2 constructors being leaked.

Nothing is exactly what it seems but everything with seems can be unpicked.

Thread using COleDispatchDriver always causes exception on second execution

Streifenhoernchen21-Dec-07 1:42

Streifenhoernchen

21-Dec-07 1:42

In general, what the thread does is: Creating and sending an e-mail containing a file attachment using an Outlook or Lotus Notes client (if installed on the system).
Running the thread once always works fine, and it terminates correctly. However, when i try to run it for a second time, it throws an exception in MFC42.DLL, unfortunately not always at the same code line, but more or less randomly, esp. during manual debugging:

UINT CommonSendMailThread(LPVOID pParam)<br />
{<br />
   //pParam is a user-defined struct containing the necessary credentials<br />
   //like recipient address, file attachment path and name, and so on...<br />
<br />
   //a global variable sType defines the user's default mail client app<br />
   //user has "Outlook" as default<br />
   if (sType == "%OUTLOOK%") {<br />
      try {	<br />
         _DApplication OutlookHandle;	<br />
			<br />
         // Initialize OLE libraries<br />
         if (!AfxOleInit())<br />
            return 1;<br />
         else {   //try to find the installed version of Outlook<br />
            if (OutlookHandle.CreateDispatch("Outlook.Application.8") == FALSE) {<br />
               // check for Outlook 2000<br />
               if (OutlookHandle.CreateDispatch("Outlook.Application.9") == FALSE) {<br />
                  // check for Outlook XP<br />
                  if (OutlookHandle.CreateDispatch("Outlook.Application.10") == FALSE) {<br />
                     // Outlook ???<br />
                     if (OutlookHandle.CreateDispatch("Outlook.Application.11") == FALSE) {<br />
                        // Outlook ???????<br />
                        if (OutlookHandle.CreateDispatch("Outlook.Application.12") == FALSE) {<br />
                           return 1;<br />
         }}}}}}<br />
<br />
         // Outlook dispatch created successfully	<br />
         _DMailItem	newMail;<br />
<br />
         // create a new mail<br />
         newMail = OutlookHandle.CreateItem(0);<br />
<br />
         //fill the mail...<br />
         //(...)<br />
         //and send it			<br />
			<br />
         newMail.Send();<br />
<br />
         OutlookHandle.ReleaseDispatch();<br />
      }<br />
<br />
      catch(...) {<br />
         return 1;<br />
      }<br />
   } // OUTLOOK<br />
<br />
   //user has "Lotus Notes" as default<br />
   else if (sType == "%NOTES%") {<br />
      try {<br />
         if (!AfxOleInit())<br />
            return 1;<br />
<br />
         NOTESSESSION *pNotesSes = NULL;<br />
         NOTESDATABASE *pNotesDB = NULL;<br />
         NOTESDOCUMENT *pNotesDoc = NULL;<br />
         NOTESRICHTEXTITEM *pNotesRichTextItem = NULL;<br />
<br />
         // pointer to new NotesSession<br />
         pNotesSes = new NOTESSESSION;<br />
<br />
         if ( !pNotesSes )<br />
            return 1;<br />
<br />
         if ( pNotesSes == NULL )<br />
            return 1;<br />
<br />
         if (!pNotesSes -> CreateDispatch( "Notes.NotesSession" ))<br />
            return 1;<br />
	<br />
         if ( pNotesSes -> m_lpDispatch == NULL ) {		<br />
            delete pNotesSes;<br />
            return 1;<br />
         }<br />
<br />
         //Create and fill the mail...<br />
         //(...)<br />
			<br />
         pNotesDoc ->SEND(0, COleVariant(sRecipientAddress));<br />
         pNotesDoc ->REMOVE (0);<br />
<br />
         pNotesRichTextItem ->ReleaseDispatch();<br />
         pNotesDoc ->ReleaseDispatch();<br />
         pNotesDB ->ReleaseDispatch();<br />
         pNotesSes ->ReleaseDispatch();<br />
<br />
         delete pNotesRichTextItem;<br />
         delete pNotesDoc;<br />
         delete pNotesDB;<br />
         delete pNotesSes;<br />
      }<br />
<br />
      catch(...) {<br />
         return 1;<br />
      }<br />
   } // NOTES<br />
   else {<br />
      return 1;<br />
   }<br />
<br />
   //exit the thread<br />
   return 0;<br />
}

I'm totally confused and have no idea how to solve or even access the problem. Any hint or help is greatly appreciated!

Re: Thread using COleDispatchDriver always causes exception on second execution

Nathan Holt at EMOM21-Dec-07 7:43

Nathan Holt at EMOM

21-Dec-07 7:43

Member 4760200 wrote:
In general, what the thread does is: Creating and sending an e-mail containing a file attachment using an Outlook or Lotus Notes client (if installed on the system).
Running the thread once always works fine, and it terminates correctly. However, when i try to run it for a second time, it throws an exception in MFC42.DLL, unfortunately not always at the same code line, but more or less randomly, esp. during manual debugging:

I would look up the MFC implementation of the send mail command in CDocument, and adapt the code to my purposes, rather than sending it through Outlook or Lotus Notes. If I did need to do it that way, one of the first questions I'd ask is "What exception is being thrown?" Also, in general returning 1 is not adequate for handling unknown exceptions. Terminating the whole program is more reasonable. Finally, the random nature of the exception sounds like a race condition, and since it doesn't go away when you debug, I would guess that you are calling functions that are intended to be called from only one thread for the duration of the process. I'm sorry I can't be more helpful.

Nathan

Subclassing (using MFC) a wndow under explorer process

Nishad S21-Dec-07 1:38

Nishad S

21-Dec-07 1:38

Hi,

Isn't it possible to subclass a window in the explorer process, using CWnd::SubclassWindow() ?

My intention is to skin the systray clock.

What I did:

1. Created a MFC dll.
2. Injected it to the explorer process using "CreateRemoteThread - LoadLibrary" technique.
3. Took the window handle of systray clock in the dll's InitInstance.
4. Replaced the window proc using SetWindowLong.

These were successful, and in the replaced proc, I could do the custom draw by processing WM_PAINT.

The problem:

I derived a class from CWnd, say CMyClock. And subclassed the systray clock window with CMyClock object (member) instead of proc replacement. Now the explorer crashes.

I tried to debug the explorer process.

I found that subclassing is fine, and InitInstance completed successfully. After a very little time it crashed and the call stack was as follows...

	ntdll.dll!7c901230() 	
>	msvcr71d.dll!_CrtDbgBreak()  Line 93	C
 	msvcr71d.dll!_CrtDbgReport(int nRptType=2, const char * szFile=0x01b44c68, int nLine=384, const char * szModule=0x00000000, const char * szFormat=0x00000000, ...)  Line 427	C
 	mfc71d.dll!AfxAssertFailedLine(const char * lpszFileName=0x01b44c68, int nLine=384)  Line 28 + 0x14	C++
 	mfc71d.dll!AfxWndProc(HWND__ * hWnd=0x000f01c8, unsigned int nMsg=15, unsigned int wParam=0, long lParam=0)  Line 384 + 0x15	C++
 	MyClockDll.dll!AfxWndProcDllStatic(HWND__ * hWnd=0x000f01c8, unsigned int nMsg=15, unsigned int wParam=0, long lParam=0)  Line 53 + 0x15	C++
 	user32.dll!7e418734() 	
 	user32.dll!7e418816() 	
 	user32.dll!7e41b4c0() 	
 	user32.dll!7e41b50c() 	
 	ntdll.dll!7c90eae3() 	
 	user32.dll!7e4194d2() 	
 	user32.dll!7e41b530() 	
 	user32.dll!7e42d950() 	
 	user32.dll!7e418a10() 	
 	user32.dll!7e42dbbf() 	
 	user32.dll!7e42593f() 	
 	user32.dll!7e43a91e()

What could be wrong? Any suggestions or ideas?

Thanks in advance.

- NS -
[ODBaseBtn]

Reference are always lvalue?

George_George21-Dec-07 1:11

George_George

21-Dec-07 1:11

Hello everyone,

Is the conclusion correct? Both const reference and non-const reference are lvalue?

I think it is true and I can not find a sample which does not follow it.

thanks in advance,
George

Re: Reference are always lvalue?

Budric B.21-Dec-07 5:09

Budric B.

21-Dec-07 5:09

I suppose if you're returning a reference from a function then it's not an lvalue.

Re: Reference are always lvalue?

George_George21-Dec-07 19:16

George_George

21-Dec-07 19:16

Thanks Budric,

Could you show a sample please?

regards,
George

how to get the number of lines shown in editbox

rajneshmalik21-Dec-07 1:06

rajneshmalik

21-Dec-07 1:06

hi to all
i want to get the number of lines shown in editbox.
thank u

Re: how to get the number of lines shown in editbox

CPallini21-Dec-07 3:05

CPallini

21-Dec-07 3:05

Win32?
Look at EM_GETLINECOUNT message documentation http://msdn2.microsoft.com/en-us/library/bb761586.aspx[^]

MFC?
look at CEdit::GetLineCount method documentation http://msdn2.microsoft.com/en-us/library/bb761586.aspx[^]

Smile | :)

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.

[my articles]

Datashowing problem want to get rid of from if-else statement

Y_Kaushik20-Dec-07 23:53

Y_Kaushik

20-Dec-07 23:53

Hello...guru's

I am writing a program in VC++ its database related application.
In this case i fetch data from Oracle database.using CRecordset class.

When i write below code
no_field = rs.GetODBCFieldCount();
while(!rs.IsEOF())
{
for(i=0;i<no_field;i++)
{
rs.GetFieldValue(i,sString);
if(i==0)
{
SetDlgItemText(IDC_EDIT_DATE1,sString);
}
if(i==1)
{
SetDlgItemText(IDC_EDIT_DATE2,sString);
}
if(i==2)
{
SetDlgItemText(IDC_EDIT_UPDT,sString);
}
}
sString.Empty();
rs.MoveNext();
}

Although above code is work fine.........
but i want to get rid of from if else condition.....This method is fine for fetching certain field from database .But if table contain 200 or more entity in a row then i need to write 200 or more if else condition...

Can any one give me berief idea how can i do this apart from this way.........

Thanks in Advanced

Regard's
Kaushik

Re: Datashowing problem want to get rid of from if-else statement

Hamid_RT21-Dec-07 0:02

Hamid_RT

21-Dec-07 0:02

Instead use of if you can use of switch.
Switch(i)
{
case 0:
break;
case 1:
break;
default:
break;
}

Re: Datashowing problem want to get rid of from if-else statement

Cedric Moonen21-Dec-07 0:13

Cedric Moonen

21-Dec-07 0:13

And how can he get rid of the 200 tests conditions by using a switch ? Unsure | :~

Cédric Moonen
Software developer

Charting control [v1.2]

Re: Datashowing problem want to get rid of from if-else statement

Cedric Moonen21-Dec-07 0:11

Cedric Moonen

21-Dec-07 0:11

Open the resource file and give adjacent Id's for your controls. This, way, you can simply do something like this:

SetDlgItemText(IDC_FIRST_CTRL_ID+i,sString);

Cédric Moonen
Software developer

Charting control [v1.2]

Re: Datashowing problem want to get rid of from if-else statement

Matthew Faithfull21-Dec-07 0:11

Matthew Faithfull

21-Dec-07 0:11

Two things you could do here.

Use a switch statement

<br />
switch i<br />
{<br />
  case 1:<br />
   //Do stuff<br />
   break;<br />
  case 2:<br />
    //Do other stuff<br />
   break;<br />
}<br />

but I wouldn't recommend that if you really have 200 fields and 200 controls on your dialog. If that's the case the easiest way is to ensure the values of your control id's are sequential and then do something like this

<br />
for(i=0;i<no_field;i++)<br />
{<br />
  rs.GetFieldValue(i,sString);<br />
  SetDlgItemText( BASE_FIELD_CONTROL_ID + i, sString);<br />
  sString.Empty();<br />
  rs.MoveNext();<br />
}<br />

you might want to use different ranges based on field/control types and use a switch to change the SetDlgItemText call.

Nothing is exactly what it seems but everything with seems can be unpicked.

Re: Datashowing problem want to get rid of from if-else statement

Y_Kaushik21-Dec-07 19:08

Y_Kaushik

21-Dec-07 19:08

Thanks for reply ....
I follow second method... give the control adjacent
like IDC_CONTROL , IDC_CONTROL+1, IDC_CONTROL+2, and so on...

and i am very near to solve problem...

Thanks again for reply to all's

Note : Is it possible for me to get control handle at run time.

Regard's
Kaushik

Dynamically providing version information to a exe

neha.agarwal2720-Dec-07 22:50

neha.agarwal27

20-Dec-07 22:50

Hi all,

Actually i want to give my exe, version number, copyright information dynamically. Is it poosible to do so.....

Re: Dynamically providing version information to a exe

jhwurmbach20-Dec-07 23:08

jhwurmbach

20-Dec-07 23:08

How dynamic is "dynamically"?

Here, our build-server includes a small, generated file with a version resource in the main resources of the project.
That way, the version number is set automagically.

Let's think the unthinkable, let's do the undoable, let's prepare to grapple with the ineffable itself, and see if we may not eff it after all.
Douglas Adams, "Dirk Gently's Holistic Detective Agency"

Re: Dynamically providing version information to a exe

C^hris L^osinger21-Dec-07 5:45

C^hris L^osinger

21-Dec-07 5:45

you mean the stuff that shows up in the Explorer Properties page after you right-click on the EXE's icon ?

no, that's not possible.

that stuff comes from examining the EXE file directly, not from executing the EXE in any way.

image processing toolkits | batch image processing

Checking the camera is connecte or not

Deepu Antony20-Dec-07 22:26

Deepu Antony

20-Dec-07 22:26

pls help me...

I am connecting a webcam to my computer thorugh usb port.can anybody help me to write a code in vc++ or c++ to check whether the camera is connected or not.

"imapi.h" file missing - SDK version

palanirajan20-Dec-07 22:04

palanirajan

20-Dec-07 22:04

hi all.,
as part of my MFC app i have to write data into CD ROM., for that i got code form Microsoft , it is purly in win 32 -SDK, fine

they have used "Imapi.h" header file form SDK, but i dont have latest version of SDK in my XP machine, but i installed SP2, i try to download form Microsoft., fine

but i was not able to install the version of SDK,

can any one help me to get latest version of SDK (XP) or if any one have "imapi.h" header file, just send it to me

thanks
shiva

Re: "imapi.h" file missing - SDK version

ashishbhatt20-Dec-07 22:12

ashishbhatt

20-Dec-07 22:12

TRY TO DOEWNLOAD THIS FILE FROM BELOW LINK...

http://www.koders.com/cpp/fid6830CE30A8B1F9A1FBADC74CBDFCDD478004ECB6.aspx?s=Imapi.h[^]

Thanks.

Re: "imapi.h" file missing - SDK version

Cedric Moonen20-Dec-07 22:27

Cedric Moonen

20-Dec-07 22:27

palanirajan wrote:
if any one have "imapi.h" header file, just send it to me

That's stupid. What will you do with a header file but no correct library file ?
The only correct thing to do is to download the required platform SDK from microsoft. So, what problem are you having there ?

Cédric Moonen
Software developer

Charting control [v1.2]

system tray - right click option

Paulraj G20-Dec-07 21:28

Paulraj G

20-Dec-07 21:28

hi everyone.....

am having my icon in system tray.......

if i right click the icon there should be some options...

how to add right click functions?

can help anyone?

thangs....

regards,
Paul.G

paulraj

Re: system tray - right click option

ashishbhatt20-Dec-07 21:47

ashishbhatt

20-Dec-07 21:47

If you are Win32 or not but you can make new resoure in which you can create new Menu and you can add it to that icon.

You can process that menu items by making window procedure to handle those menu messages.

Re: system tray - right click option

Paulraj G20-Dec-07 23:27

Paulraj G

20-Dec-07 23:27

hi...

can you tell somewhat briefly...

paulraj

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