Re: Static destructors called after main - C / C++ / MFC Discussion Boards

Re: Create a WinZip file and is there a way to prevent winzip from reading it

Jonathan Craig26-Feb-03 4:11

26-Feb-03 4:11

If you want custom stuff you can use the PKWARE Data Compression Library. I have use them before to compress very large amounts of data. They allow you to create your own file formats and use PKZIP quality compression.

http://www.pkware.com/products/developers/dcl/

Jonathan Craig
www.mcw-tech.com

Dao Classes

Anonymous26-Feb-03 1:29

Anonymous

26-Feb-03 1:29

Hi,

I'm creating a program that does the following:

- create an Access database using CDaoDatabase
- create in this db a table with a number of fields, for which I use CDaoTableDef

So far, no problem.
But now I need to insert data into de table, and I cna't figure out how.
Could anybody show me some code to do this?

Thanks

n

Re: Dao Classes

includeh1026-Feb-03 2:36

includeh10

26-Feb-03 2:36

move to place u want to add new data

//i can't remember exact name of each function
1. call New() (?)
2. Add(),Add(),..., add whole row
3. call Update()

New() locks ur table
Update() ends the action and put data into table

if edit then step 1 is Edit()

by the way, VB is wanderful for database, and easy to learn, C++ is too complex for database.

includeh10

Re: Dao Classes

Anonymous26-Feb-03 3:03

Anonymous

26-Feb-03 3:03

Excuse me,

your New() function is a member of which DAO class? where can I find it?

Thanks

Re: Dao Classes

includeh1026-Feb-03 6:49

includeh10

26-Feb-03 6:49

i can't remember exact name of each function as i said, but u definitely can find similar function.

if u can't, i will find for u tommorow.
it should belong to Table or RecordSed class.

includeh10

Re: Dao Classes

Anonymous27-Feb-03 21:36

Anonymous

27-Feb-03 21:36

I finally solved it wil CDaoTableDef!

Thanks

Static destructors called after main

krisn26-Feb-03 1:23

krisn

26-Feb-03 1:23

I have a static instance of a class that basically handles memory allocation for a certain module. This way when the application quits this destructor will handle freeing memory for the whole module. An alternative would be to call an 'exit' type function in this module to do a similar thing.

As this is a static object, the constructor and destructor get called before and after calling 'main()'. However in the main() function just before we return, we call our own CheckMemory function that checks all allocated memory has been freed (we also have out own new & delete functions for this). As the memory in my module is not freed until the destructor we get a few warnings.

Any ideas as to how to fix this?

I am considering putting the CheckMemory() into it's own class and call the check in the destructor but how can we guarantee when each destructor will be called?

Is there a Visual C++ 'work around' for this problem?

Thanks

Kris

Re: Static destructors called after main

Joaquín M López Muñoz26-Feb-03 1:41

Joaquín M López Muñoz

26-Feb-03 1:41

C++ does not guarentee any particular order of static initialization across compilation units (different .cpps in plain English). But there's a nifty trick to ensure that a given static constructor is executed the first in your program, and hence its destructor is called the very last:

// memorychecker.h
 
class memory_checker
{
  memory_checker();
  ~memory_checker()
  {
    CheckMemory();
  }
public:
  static void launch()
  {
    static memory_checker mc;
  }
};
 
struct memory_checker_laucher
{
  memory_checker_laucher()
  {
    memory_check::launch();
  }  
};
 
static memory_checker_launcher mcl__;

Now, if you #include "memorycheck.h" at the beginning of every .cpp of your program, you will get CheckMemory to be called when everybody else has left the party.

Joaquín M López Muñoz
Telefónica, Investigación y Desarrollo

memory problem!

Gérald Mercet26-Feb-03 1:18

Gérald Mercet

26-Feb-03 1:18

Hi everybody,

Perhaps a simple question but, i would like to suggest it o you:

In my application, i have an "access violation" message which appear to this following line:

*(pHistoDBNorm+ j- *(pInflex+i)- *pInflex), when i=0 and j=16, just with this indications, you will tell me to check if th e allocation is well done, but the problem is if i remove *(pInflex+i)- *pInflex (which is equal to 0), in the debug window, the following
*(pHistoDBNorm+ j) is evaluated correctly whereas
*(pHistoDBNorm+ j- *(pInflex+i)- *pInflex), always in the debug window couldn't be evaluated (instead of reading a value which would have to be the same than *(pHistoDBNorm+ j), i could read something like that:"expression couldn't be read..."

why??????

thanks in advance

gerald

Re: memory problem!

Joaquín M López Muñoz26-Feb-03 1:24

Joaquín M López Muñoz

26-Feb-03 1:24

All clues suggest that pInflex is invalid. Maybe you have freed it before time?

Joaquín M López Muñoz
Telefónica, Investigación y Desarrollo

Re: memory problem!

Gérald Mercet26-Feb-03 1:27

Gérald Mercet

26-Feb-03 1:27

i'm not sure because i have tested at the same time and both *pInflex and *(pInflex+i) have a correct value (equal to 0). i have seen it in the debug window!

Re: memory problem!

Joaquín M López Muñoz26-Feb-03 1:30

Joaquín M López Muñoz

26-Feb-03 1:30

Wait! There's a typo in your expression, instead of

*(pHistoDBNorm+ j- *(pInflex+i)- *pInflex)

it should be

*(pHistoDBNorm+ j- <font color=#ff0000>(</font>*(pInflex+i)- *pInflex<font color=#ff0000>)</font>)

Joaquín M López Muñoz
Telefónica, Investigación y Desarrollo

Re: memory problem!

Gérald Mercet26-Feb-03 4:31

Gérald Mercet

26-Feb-03 4:31

you're right, sorry for this stupid mistake and thanks for your help

Re: memory problem!

Gérald Mercet26-Feb-03 1:33

Gérald Mercet

26-Feb-03 1:33

Sorry just a little mistake in my answer: "both *pInflex and *(pInflex+i) have a correct value (equal to 15)", not really important i know, but..!

How do you drag & drop an icon in VC++6?

Damien McGauley26-Feb-03 1:03

Damien McGauley

26-Feb-03 1:03

Hi Folks I'm pretty new to this ao any help would be very much appreciated. I'm building a Dialog based application which carries out some maths on the user input.

Would anyone be able to give me a simple example of how to drag an Icon within a defined rectangle in a Dialog based application? I need to be able to monitor the x,y position of the Icon. I think I need to use WM_LBUTTONDOWN and WM_LBUTTONUP messages but I'm not sure of the easiest way to do it.

I'm using Windows 98 and Visual C++ 6

Thanks in advance

Damien

WM_MOUSEHOVER

zeki yugnak25-Feb-03 23:48

zeki yugnak

25-Feb-03 23:48

hi..

how to use WM_MOUSEHOVER,I have not seen more example about this message.
I am using Win32api,not mfc.

I want to get button's text when mouse cursor on button.not push or select.
please help!!!

Re: WM_MOUSEHOVER

vikramlinux26-Feb-03 0:00

vikramlinux

26-Feb-03 0:00

I think you can make WM_MOUSEMOVE Work. and jast say GetWindowFromPoint().check for the class name of button..and then GetwindowText..what do you say?

Re: WM_MOUSEHOVER

vikramlinux26-Feb-03 0:02

vikramlinux

26-Feb-03 0:02

Sorry WindowFromPoint and not the GetWindowFromPoint

Re: WM_MOUSEHOVER

zeki yugnak26-Feb-03 1:18

zeki yugnak

26-Feb-03 1:18

hi vikrams...

thanks for your reply.. Smile | :)

I have a new problem.this program is working when cursor on window but not working for button or any controls. Confused | :confused:

have you got any suggestion?

Re: WM_MOUSEHOVER

vikramlinux26-Feb-03 18:10

vikramlinux

26-Feb-03 18:10

Can you paste the Code snippet here,that you are using ?

Re: WM_MOUSEHOVER

zeki yugnak27-Feb-03 8:30

zeki yugnak

27-Feb-03 8:30

Hi...

My code is follow:

case WM_MOUSEMOVE:
GetCursorPos(&pt);
hControl=WindowFromPoint(pt);
GetWindowText(hControl,str,30);
if(hControl==GetDlgItem(hWnd,IDOK))
MessageBox(hWnd,str," ",0);
else if(hControl==hWnd)
MessageBox(hWnd,str,"",0);
return TRUE;

Problem of "\r\n"

adapterJohn25-Feb-03 22:49

adapterJohn

25-Feb-03 22:49

Hello, I am writing a very small function to display the status of my application. Every time I get a new status I want to change to a new line and display it, that's why Status+="\r\n" is there. But strangely the program doesn't change to new line, instead, it display a "II" so all my message are showing in the same line.
Can someone help me to figure out the problem?
Many thanks in advance,

void CAPIDlg::DisplayStatus(CString aCString){
Status+=aCString;
Status+="\r\n";
m_Status.SetWindowText(Status);

}

aCS

Re: Problem of "\r\n"

peterchen25-Feb-03 23:05

peterchen

25-Feb-03 23:05

Make sure the control has the mutiline style (if it's an EDIT), or neither the "centered" nor "simple" style (if it's a STATIC).

If you go to war, you will destroy a great country a stoned greek chick to the richest man of the world

[sighist] | [Agile Programming] [doxygen]

Re: Problem of "\r\n"

KarstenK25-Feb-03 23:08

KarstenK

25-Feb-03 23:08

You see the ASCII Output of "\r\n".
Check that your control is multiline enabled.
Try Status.Format( %s\r\n", aCString )
Wink | ;)

Try this @ home. (B&B)

Re: Problem of "\r\n"

adapterJohn26-Feb-03 0:07

adapterJohn

26-Feb-03 0:07

Ya! I adjust the mutiline option and it works fine now Smile | :)

Thanks!

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