C / C++ / MFC Discussion Boards

modular29-Jul-03 3:53

29-Jul-03 3:53

I am conecting to MYSQL database which is on the server using following code.

CDatabase m_dbftp;
m_dbftp.OpenEx(sDSNName,CDatabase::noOdbcDialog | CDatabase::useCursorLib );

Connection is done properly. I want to catch the exception
when server is disconnected.
I am using following code
catch(CDBException* pEx )
{
CString sz;
if ( pEx->m_nRetCode == AFX_SQL_ERROR_CONNECT_FAIL )
AfxMessageBox("myconnection failed");
}

It dose not work
Problem is m_nRetCode contains -1 instead of
AFX_SQL_ERROR_CONNECT_FAIL .

I am not able to identify if server is disconnected .? How to do it.

Strange Codes

FlyingDancer29-Jul-03 3:50

FlyingDancer

29-Jul-03 3:50

I see a sentence like below:
private Mutex[] m_mutex;
It seems very strange for me
What is its meaning?
Help
Thank you

Re: Strange Codes

⁷³Zeppelin29-Jul-03 5:45

⁷³Zeppelin

29-Jul-03 5:45

Short for MUTual EXclusion. These are used to non-recursively synchronize access to shared resources. Eg: in order to protect a critical section, you can use a mutex, which will ensure that only one thread at a time can lock it.

Re: Strange Codes

David Crow29-Jul-03 7:37

David Crow

29-Jul-03 7:37

It looks like a syntax error to me. The private keyword should have a colon after it, and the square brackets should follow the variable, not the type.

private:
    Mutex m_mutex[];

If it's something different, it's new to me.

Re: Strange Codes

armentage29-Jul-03 8:24

armentage

29-Jul-03 8:24

DavidCrow wrote:
It looks like a syntax error to me. The private keyword should have a colon after it, and the square brackets should follow the variable, not the type.

private: Mutex m_mutex[];

If it's something different, it's new to me.

I think that's Java, or may C#. In Java, you denote the accessability of each member explicitly. Correct me if I'm wrong, its been a while since I used Java, arrays of a type are written as TypeName[] variableName.

Re: Strange Codes

David Crow29-Jul-03 8:32

David Crow

29-Jul-03 8:32

Good call, thanks.

Re: Strange Codes

FlyingDancer29-Jul-03 14:39

FlyingDancer

29-Jul-03 14:39

You can find the codes at the following site:
http://www.codeproject.com/useritems/inprocsemaphore.asp?target=semaphore

Re: Strange Codes

David Crow29-Jul-03 16:49

David Crow

29-Jul-03 16:49

Shouldn't C# questions be posted to the C# forum instead of the VC++ forum? You're bound to get more answers that way!

Set Fullscreen mode

soundman3229-Jul-03 3:39

soundman32

29-Jul-03 3:39

Is there any way to programatically set/unset fullscreen console mode?

Neil

Re: Set Fullscreen mode

zeki yugnak29-Jul-03 4:26

zeki yugnak

29-Jul-03 4:26

hi..

this way is not exactly same yours however you can use.

//ID_VIEW_FULLSCREEN on menu<br />
<br />
void CMainFrame::OnViewFullscreen() <br />
{<br />
	if (m_fullscreen)<br />
	{<br />
		ModifyStyle(0,WS_CAPTION|WS_THICKFRAME);			<br />
		ShowWindow(SW_SHOWNORMAL);<br />
<br />
		ShowControlBar(&m_wndToolBar, TRUE, FALSE);<br />
		ShowControlBar(&m_wndStatusBar, TRUE, FALSE);<br />
	}<br />
	else<br />
	{<br />
		ModifyStyle(WS_CAPTION|WS_THICKFRAME,0);			<br />
		ShowWindow(SW_MAXIMIZE);<br />
<br />
		CFrameWnd* pChild = GetActiveFrame();<br />
		if (pChild)	pChild->ShowWindow(SW_MAXIMIZE);<br />
<br />
		ShowControlBar(&m_wndToolBar, FALSE, FALSE);<br />
		ShowControlBar(&m_wndStatusBar, FALSE, FALSE);<br />
	}<br />
	m_fullscreen = !m_fullscreen;<br />
}

Re: Set Fullscreen mode

soundman3229-Jul-03 5:06

soundman32

29-Jul-03 5:06

Erm, I was after full screen mode for console (text mode) programs, not GUI

Neil

Re: Set Fullscreen mode

wb29-Jul-03 5:18

29-Jul-03 5:18

hm.. I never did it, but perhaps by finding the window of the
console. and then sending "Alt+Enter" to it?!?

Use EnumWindows(), So you can find the ConsoleWindow. it has
the name of your app in the title.
and then send the "go full screen" magic "Alt+Enter" Roll eyes | :rolleyes:

Re: Set Fullscreen mode

User 2237029-Jul-03 6:04

User 22370

29-Jul-03 6:04

Functional but not very elegant - this sends a Ctrl+Enter to the console window:

<br />
#include <windows.h><br />
#include <conio.h><br />
<br />
int _tmain(int argc, _TCHAR* argv[])<br />
{<br />
    keybd_event( VK_MENU, MapVirtualKey( VK_MENU, 0 ), 0, 0 );<br />
    keybd_event( VK_RETURN, MapVirtualKey( VK_RETURN, 0 ), 0, 0 );<br />
    keybd_event( VK_RETURN, MapVirtualKey( VK_RETURN, 0 ), KEYEVENTF_KEYUP, 0 );<br />
    keybd_event( VK_MENU, MapVirtualKey( VK_MENU, 0 ), KEYEVENTF_KEYUP, 0 );<br />
  <br />
<br />
  getch();<br />
  return 0;<br />
}

Displaced Aussie. Currently in London, normally living in Melbourne.

modified 10-Jul-19 21:02pm.

SAFEARRAY..

JoeSox29-Jul-03 3:36

JoeSox

29-Jul-03 3:36

what is a SAFEARRAY?
I am having a hard time understanding the little documentation that I have found. I am interested in constructing one because of this function I have found...

<br />
//----------------------------------------------------------------------------------------<br />
//detect objects within the image<br />
//----------------------------------------------------------------------------------------<br />
int CFacedetectApp::RCobj_detectfaces(SAFEARRAY **bmp)<br />
{  <br />
  BYTE *bmp2;<br />
  int i;<br />
<br />
  SafeArrayLock(*bmp);<br />
<br />
  bmp2 = (BYTE *)(*bmp)->pvData;<br />
<br />
  for (i=0;i<width*height*3;i++) video_image[flip]->imageData[i] = bmp2[i];  <br />
<br />
  if (!trackingEnabled)<br />
    DetectFaces(video_image[flip]);<br />
    else<br />
	updateTracking();<br />
<br />
  flip = 1-flip;<br />
<br />
  SafeArrayUnlock(*bmp);<br />
<br />
  return(NoOfObjects);<br />
}<br />

The code is from....
http://www.fuzzgun.btinternet.co.uk/rodney/components.htm#FaceDetection[^]
Why is it so hard just to give a function a simple file name and let it do it's detection Unsure | :~

I like his .dlls because they are simplified but I am having trouble understanding them. any help would be great. thanks

Later,
JoeSox
www.humanaiproject.org
"The worst fad has been these stupid little robots,
Graduate students are wasting 3 years of their lives
soldering and repairing robots, instead of making them smart.
It's really shocking." -Marvin Minsky.

Re: SAFEARRAY..

Ian Darling29-Jul-03 4:17

Ian Darling

29-Jul-03 4:17

It's sort of the VB/COM/DISPATCH array type. If you're in MFC, COleSafeArray can be used to manage SAFEARRAYs more easily.

--
Ian Darling

Re: SAFEARRAY..

JoeSox29-Jul-03 6:05

JoeSox

29-Jul-03 6:05

Ian Darling wrote:
It's sort of the VB/COM/DISPATCH array type. If you're in MFC, COleSafeArray can be used to manage SAFEARRAYs more easily.

ah, perfect thanks, I'll start reading up on COleSafeArray. Smile | :)

Later,
JoeSox
www.humanaiproject.org
"The worst fad has been these stupid little robots,
Graduate students are wasting 3 years of their lives
soldering and repairing robots, instead of making them smart.
It's really shocking." -Marvin Minsky.

CDC BitBlt problem

_crs_29-Jul-03 3:12

_crs_

29-Jul-03 3:12

hello,
I have a big problem ... I have created a MFC app from wizard ... and added:
void CEditorView::OnInitialUpdate()
{
CScrollView::OnInitialUpdate();

CSize sizeTotal;
// TODO: calculate the total size of this view
sizeTotal.cx = widthMM;
sizeTotal.cy = heightMM;
SetScrollSizes(MM_LOMETRIC, sizeTotal);
}
so, my maping mode is MM_LOMETRIC ...
and in OnDraw ....

void CEditorView::OnDraw(CDC* pDC)
{
CEditorDoc* pDoc = GetDocument();
ASSERT_VALID(pDoc);
// TODO: add draw code for native data here

CDC bdc;
bdc.CreateCompatibleDC(pDC);
CBitmap cb;

cb.CreateCompatibleBitmap(pDC, 1000,1000);
bdc.SelectObject(cb);
bdc.SelectStockObject(WHITE_BRUSH);
bdc.PatBlt(0,0,1000, 1000, PATCOPY);
bdc.SelectStockObject(BLACK_BRUSH);
bdc.Rectangle(CRect(0, 0, 500, -500));

pDC->StretchBlt(0, 0, 1000, 1000, &bdc, 0, 0, 1000, 1000, SRCCOPY);
}

and nothing happens .... why ?????
I tried to change the sign of the coordonate values and still nothing ...

How can I create a compatible DC with my DC and to paint in it ?????
please help !!!.... thanks ......

Hmmm, it should have worked...

Kochise29-Jul-03 4:30

Kochise

29-Jul-03 4:30

...but I not took real time to dig your code enough !

BTW, have a look at my own code (which work in every case), and find out how it works Wink | ;)

Tips, look in CSkinProgress::OnPaint() !

http://www.codeproject.com/miscctrl/CSkinProgress.asp

Kochise

PS : Use CSkinProgress::ConvBitmap(...) to convert your bitmap from another color map if for instance, you are trying to display a 24 bits/pixel picture on a 16 or 32 bits/pixel screen ! Otherwise you'll get a black/blank screen instead !

In Cod we trust !

Re: CDC BitBlt problem

C^hris L^osinger29-Jul-03 5:36

C^hris L^osinger

29-Jul-03 5:36

bdc.SelectObject(cb);

try

bdc.SelectObject(&cb);

-c

CheeseWeasle

Debug Assertion Failed

Luke Murray29-Jul-03 3:06

Luke Murray

29-Jul-03 3:06

Hello everyone.

i'm i got a program that uses the drag and drop class from CP (i think Leon Finker's) and i'm not sure whats causing it, but when in debug mode i drag something from one listview to another, i get "Debug Assertion Failed" on line 1132 of dbgheap.c something about _CtrlsValidHeapPointer(pUserData) and "Damage: before Normal block (#-858993460) at 0x0012D1D8"

I'm have no idea how this is happening, and why, i was hoping someone could help, me, even a good article on debuging would be nice. I'm using WTL as well.

Even when i have the onDrop method do nothing i still run into this error, i can get to line 1186 in dbgheap.c then it wont do anything but break out of running. Its something to do with freeing debug memory from the heap. anybody know anything that could help me?

thanks

Luke.

Re: Debug Assertion Failed

Michael Dunn29-Jul-03 5:05

Michael Dunn

29-Jul-03 5:05

Luke Murray wrote:
Damage: before Normal block (#-858993460) at 0x0012D1D8

You (or some code you're using) allocated memory, then wrote outside of the block of memory. In this case, it underran the block and the CRT detected it.

--Mike--
Ericahist | Homepage | RightClick-Encrypt | 1ClickPicGrabber
Latest art~!@#2rDFA#@(#*%$Rfa39f3fqwf--=
NO CARRIER

Re: Debug Assertion Failed

Luke Murray29-Jul-03 21:18

Luke Murray

29-Jul-03 21:18

Thanks Michael, that made some sense, and after some more looking into the code, i got it fixed.
Thanks for the reply

Luke.

#region in vc?

novachen29-Jul-03 2:01

novachen

29-Jul-03 2:01

Hi!
region is very useful feature in c#. By region, we can organize long file easily.
is there such a feature in vc7?
I know vc7 will hide or show class or method. But does it have a region feature, i hope to use it to split my long #define list manually.

Re: #region in vc?

Alexander ^M.,29-Jul-03 9:22

Alexander ^M.,

29-Jul-03 9:22

i had a look at the preprocessor command list in msdn and didn't find anything like that!
sorry guy

Don't try it, just do it! Wink | ;-)

Print a postscript file

Jerome Conus29-Jul-03 2:01

Jerome Conus

29-Jul-03 2:01

Hi !

I have a postscript file on my harddisk, and I want my application to send it to the printer. I've got no idea how I can do this, if possible using only standard C++ (I'd like my app to be platform independent).

Thank you for your help !
Jerome

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