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example code:
char *temp;
temp = new char [LENGTH];
while(true)
{
temp = "testing123";
delete temp;
}
Q - how to free the memory allocate to the pointer?
how to free the array but not delete the pointer?
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You cannot use new and delete in this way.
the instruction temp="testing123"; will change the adress contained in the pointer. So when you try to delete it, it will assert because the pointer to the "testing123" string wasn't dynamically allocated.
You'll have to change to this:
while(true)<br />
{<br />
strcpy(temp,"testing123");<br />
<br />
delete temp;<br />
}<br />
This will copy the data in the temp pointer (WITHOUT changing it's adress).
Hope this is clear enough 
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wrong, wrong, wrong!!!
you can't implement such a loop, when the memory is freed, you can't free it a second time!
Don't try it, just do it! 
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Oooooooooooooooooooooooops !!
Sorry I wrote it too fast 
I wanted to say this:
while(true)<br />
{<br />
strcpy(temp,"testing123");<br />
}<br />
delete temp;<br />
The delete is of course outside of the loop !
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Hello,
I use the ODBC driver "dBase Files" (installed on my station by microsoft application, I guess).
hereunder is the code I wrote to access the C:\Documents and Settings\dd\Mes documents\GSTAT.DBF file :
#define DBName "DSN=dBASE Files;UID=WD:"
...
CDatabase gDB;
CRecordset rs(&gDB);
CString res;
CString ErrMsg;
CString CASHT;
CString NETROOM;
CString DATUM;
int NbRecord;
CString Path = "C:\\Documents and Settings\\dd\\Mes documents\\" ;
CString File = "GSTAT.DBF" ;
ErrMsg = "";
res = "SELECT DATUM,CASHT,NETROOM from ["+File+"]";
// res = "SELECT DATUM,CASHT,NETROOM from ["+File+"] WHERE (DATUM = 20010208)";
// res = "SELECT DATUM,CASHT,NETROOM from ["+File+"] WHERE (DATUM = '20010208')";
// gDB.OpenEx(DBName,CDatabase::noOdbcDialog);
gDB.OpenEx(DBName,CDatabase::forceOdbcDialog );
TRY
{
rs.Open( CRecordset::forwardOnly, res );
NbRecord = rs.GetRecordCount();
}
CATCH(CDBException, e)
{
ErrMsg ="**ERR: "+e->m_strError.Left(70);
}
END_CATCH
if (ErrMsg == "") {
while(!rs.IsEOF()) {
rs.GetFieldValue( "DATUM", DATUM);
rs.GetFieldValue( "CASHT", CASHT);
rs.GetFieldValue( "NETROOM", NETROOM);
rs.MoveNext();
}
}
rs.Close();
gDB.Close();
Used like this, it works but I have some problems :
1) I am obliged go thru the ODBC display to give again the name of the file, I can't set it by program ... why ? How can I do this and use the noOdbcDialog option (When I try to use it, ODBC tells me that it can't find GSTAT.DBF)?
Furthermore, ODBC dialog is based on program directory, not on the path. If I add the Path to the name in File variable, ODBC tells me that it can't find C:\Documents and Settings\dd\Mes documents\GSTAT.DBF ...
2) If I add the clause "WHERE" to my request, no record is returned ... why ? Can't I use it ? Am I obliged to read all records and test the DATUM field by program ?
3) what is the format of the date in the file ? Excel says 08/02/2001, Word says 20010208 and DATUM = 2001-02-06 when debugging my code ... When I use a date in format yyyy-mm-dd or dd/mm/yyyy ODBC tells me that my format is not compatible with data type
Thanks in advance
DD
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Qadddd wrote:
1) I am obliged go thru the ODBC display to give again the name of the file, I can't set it by program ... why ?
It sounds like the "dBASE Files" DSN is not configured correctly. If it was, there would be no reason to specifiy filenames, database names, paths, etc in your code.
Assuming the database exists, you can create the DSN programatically by using SQLConfigDataSource(NULL, ODBC_ADD_DSN, ...).
Qadddd wrote:
res = "SELECT DATUM,CASHT,NETROOM from ["+File+"]";
I don't use .dbf files, but I think that File should be the name of a table within the database.
Qadddd wrote:
If I add the clause "WHERE" to my request, no record is returned ... why ?
What type of column is DATUM? It looks sort of like a date column, which means you use #02/08/2001# to compare against.
A rich person is not the one who has the most, but the one that needs the least.
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DavidCrow wrote:
It sounds like the "dBASE Files" DSN is not configured correctly. If it was, there would be no reason to specifiy filenames, database names, paths, etc in your code.
yes, as I said myself before, I just discover on ODBC pannel the check saying that the current directory is the home directory for my file, I will go deeper in investigations tonight
DavidCrow wrote:
Assuming the database exists, you can create the DSN programatically by using SQLConfigDataSource(NULL, ODBC_ADD_DSN, ...).
that's a good point ! because when I put my little applications on several stations, I always have to configure manually ODBC, I could do it in a little installation executable. The same, if you have a piece of advice to automate the installation of a new ODBC driver ... I take it .
DavidCrow wrote:
I don't use .dbf files, but I think that File should be the name of a table within the database.
That's what my MySQL statement looks like, but for .dbf files ?? I looked at 2 or 3 examples using this syntax and it seems that I can access the file like this without too many problems ... 2 good reasons to keep it like that until someone tells me that my manner is totally wrong )
DavidCrow wrote:
It looks sort of like a date column, which means you use #02/08/2001# to compare against.
It's probably the reason, I will test it ASAP
Thanks
DD
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I am having great difficulty getting pointers to GDI+ objects working in Doc/View under VC6.
The section of code from a Doc/View implementation (Wizard generated, no changes made):
#define TEST_POINTER
void CTestView::OnDraw(CDC* pDC)
{
CTestDoc* pDoc = GetDocument();
ASSERT_VALID(pDoc);
#ifdef TEST_POINTER
Graphics* graphics = new Graphics(pDC->m_hDC);
Pen* pen = new Pen(Color(255, 0, 0, 0));
graphics->DrawLine(pen, 50, 50, 350, 550);
graphics->DrawRectangle(pen, 50, 50, 300, 500);
graphics->DrawEllipse(pen, 50, 50, 300, 500);
delete pen;
delete graphics;
#else
Graphics graphics(pDC->m_hDC);
Pen pen(Color(255, 0, 0, 0));
graphics.DrawLine(&pen, 50, 50, 350, 550);
graphics.DrawRectangle(&pen, 50, 50, 300, 500);
graphics.DrawEllipse(&pen, 50, 50, 300, 500);
#endif
}
compiles when TEST_POINTER is UNDEF'd but not when it is defined. I get the error message "error C2660: 'new' : function does not take 3 parameters" for the two 'new' functions.
As far as I can see the global new function is being called instead of the operator::new that the classes implement.
Can somebody tell me how to use GDI+ class pointers ? I need to use pointers as I am implementing pen/brush caches in a CAD.
Any advice would be greatly appreciated.
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Sorry, found the answer.
The solution is to get rid of '#define new DEBUG_NEW' in the source file(s) where the pointers are used.
Apologies for any time wasted.
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Can I retrieve a pointer to the listbox of a combobox in CBS_DROPDOWNLIST style?
I'd like to change the dropped rect, but unfortunately there is no SetDroppedRect().
The thing is that the strings in the list are to long to display fully onto the screen. Therefore I am obliged to use the horizontal scrollbar. The problem is that the vertical height of the dropped list is adjusted to the count of items, when the total item-height is smaller than the created combobox height.
In case of 1 item (very large string) the horizontal scroll bar is invisible.
In case of 2 items the second item is covered by the scroll bar. This does not look nice!! It seems that the height of the horizontal scroll bar is not taken into account during the making of the Dropped list box.
Does anyone have a solution like retrieving a pointer to the listbox to adjust height. All help is welcome.
Toon Schellinck
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Hi !
I'm wondering how a bool type is supposed to work regarding boolean operations :
If I do this :
bool a=true;
bool b=false;
b&=a;
It is working, but is it a coincidence (because & is a bitwise operation) ? Or am I supposed to do :
b&&=a;
or
b=b && a;
????
What do you think ?
Jerome
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Jerome Conus wrote:
...because & is a bitwise operation) ?
And a bool type has 8 bits!
What exactly are you trying to accomplish?
A rich person is not the one who has the most, but the one that needs the least.
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Hi guys,
I would like to know how to extract the differents formats provided in an icon?
ExtractIconEx just extract the icon but you have no control on its formats. I want for example to extract the 16x16 256Colors format of a given icon (if such format is defined in the icon). How to do that? Can any body show me the sample code for doing this? Icon editors can do this, so I guess there is a trick for that!
Thanks.
Bouli.
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Thanks, it's helpfull... 
I thought it was easier for doing this, but the code is awfull... I'm going to study this sample.
thanks again
bouli.
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My pleasure
And all the girlies say I'm pretty fly for a white guy
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hello,
i have prepared a software.i m in windows 2000 professional ...the executable file is here. how do i install in another machine remotely .the remote m/c is either windows2000 or win 98/95 ???
if anybody have code (in C++,VC++,MFC,win32) or links please inform.
please suggest some function (win32) to do that.
skpanda
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If the file is a single executable, one option is just to copy it over. If you need to make registry settings (like add your program to start-up or save it's settings during the installation), then perhaps you could utilize a Remote Desktop connection ?
Otherwise I think the best solution would be to just walk over and install the program manually. Network installations are always tricky, mostly due to firewalls and other protection schemes. No matter the mechanism, the target computer's owner should be allowed to decide whether to install the program or not.
-Antti Keskinen
----------------------------------------------
The definition of impossible is strictly dependant
on what we think is possible.
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I am trying to get handle of Edit box of Login Window of Yahoo. FindWindowEx is failing.
if(strcmpi(ClassName,"YahooBuddyMain")==0)
{ HWND hwndChildAfter,hChild;
HWND hYahooLogin = FindWindow("#32770","Login");
hChild = FindWindowEx(
hWndYahoo, // handle to parent window
hYahooLogin, // handle to a child window
"EDIT", // pointer to class name
NULL // pointer to window name
);
}
Cheers!!!!!!!!
Siddharth
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Where are you writing this code ?
in the HOOK Handler ?
Then it is possible that the login dialog is not created Yet .
Instead Wait for the creation of
#32770 (Dialog)
if you find one then check whether its parent is YahooBuddyMain
Hope it Helps
Live as if your were to die tomorrow. Learn as if you were to live forever.
-Mahatma Gandhi
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Perfect. Mission accompalished. Thanx a lot frm bottom of my heart.
Cheers!!!
Siddharth
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My pal had created a property sheet and added few pages to it. Well every thing works fine and so on.
There are three buttons Ok, Cancel & Apply. my problem is that these buttons dont have short cut keys,
so my question is how do i set a shortcut keys to those buttons.
I Touched Osama Bin Ladens Bushy Beard
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I've been considering purchasing the VS NET but i have a couple of questions before i commit.
1. Am I missing out if I don't purchase VS NET particularily if I program in C++ (MFC/ATL/WTL) as opposed to C++ in VS 6.0?
2. Is there a difference between VC++ NET Standard and the professional version when it comes to MFC/ATL/WTL programming?
I would greatly appreciate any advice. 
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Perhaps I can offer some answers..
As for the first question, the VS .NET version, especially the 2003 which I have, offer a much more flexible and working integration systems that simplify coding quite much. For example, the clumsy ClassWizard has been removed, and instead, every MFC class is considered a standard C++ class, and there is a 'properties' bar for it from which you can override virtual functions, create Windows message and event maps and so on. Generally speaking, my coding time has improved some and I can now focus more on the content itself as I don't need to worry about buggy CW files or missing virtual functions, which was a common error during the VS 6.0 times. I was constantly deleting and remaking the CW files.
Also, the VS .NET is much more flexible. The Class Bar has improved a lot, making it possible to e.x. add your own classes to the list of MFC base classes. Like, if you were to derive a custom control and would like to derive again from this control, you can move the files in question to a special directory, and then you can create descendants, override virtual functions and do custom implementation easily by using the Class View and it's properties-page.
For the second question, no, not really. The MFC/ATL/WTL libraries shipped with either the Standard or Professional editons are the same, version 7. The biggest source of differencies comes from the functionality of the IDE and the optimization/customization options of the compiler/linker. The Professional version compiler, for example, is capable of doing much greater level of optimization routines and compile-time code manipulation than the Standard version one.
As a final note, if you have enough money to invest, I suggest you go for the Professional, or even better, the Architect version. You can read more about the differences between seperate versions from the VS .NET homepage located in here[^].
-Antti Keskinen
----------------------------------------------
The definition of impossible is strictly dependant
on what we think is possible.
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