C / C++ / MFC Discussion Boards

James R. Twine13-Mar-07 3:16

13-Mar-07 3:16

   Look for places where you might be storing a pointer value returned by CString objects - this is generally a good sign that you are either using a CString incorrectly, or should not be using one in the first place.

   Things to look for:
      (LPTSTR)(LPCTSTR)sSomeCString
      sSomeCString.GetBuffer(...)

   Peace!

-=- James
Please rate this message - let me know if I helped or not!<HR>If you think it costs a lot to do it right, just wait until you find out how much it costs to do it wrong!
Avoid driving a vehicle taller than you and remember that Professional Driver on Closed Course does not mean your Dumb Ass on a Public Road!
See DeleteFXPFiles

Re: Heap Error

baerten13-Mar-07 4:00

baerten

13-Mar-07 4:00

mmh.

At the beginning i saw that it was an error with the CString ( it happens after the CString Destruktor )
But now, with the "new" error at the CObject-Destruktor of the Frame with the focus, i don't have an error at a CString. The two only CString's are destructed correctly.

if i have a

char temp[50];
and a CString str = "lalalala";

how can i put the data of str into temp;
since now i made it via strcpy(temp,str.GetBuffer());
Apart of an overflow if temp is too small i can't see a problem in this case, or ?

Thanks Smile | :)

Re: Heap Error

prasad_som13-Mar-07 4:08

prasad_som

13-Mar-07 4:08

baerten wrote:
since now i made it via strcpy(temp,str.GetBuffer());

Why you needed this ?
Doesn't CString's operator LPCTSTR suffice ?

Prasad
Notifier using ATL | Operator new[],delete[][^]

Re: Heap Error

baerten13-Mar-07 4:42

baerten

13-Mar-07 4:42

i remake an existing DOS-Application into a MFC-FrontEnd.
I need to use the existing functions, which are working with char*

Re: Heap Error

James R. Twine13-Mar-07 5:03

James R. Twine

13-Mar-07 5:03

You can just do:

strcpy(temp,str);

   But you should really be using n-versions of the string functions to make sure you do not overrun the temp buffer.

   Note that a CString can be used in place of a const char * or LPCSTR/LPCTSTR, so you generally do not need to copy its contents to a char buffer unless the string data is being used in a non-const fashion.

   Carefully examine any places where you are using CString::GetBuffer(...) - it usually means that something strange is going on. If you have to use CString::GetBuffer(...), you likely should not be using a CString in that situation (not to mention that calls to it should be wrapped in a try/catch for exception handling).

   Peace!

Re: Heap Error

baerten13-Mar-07 23:35

baerten

13-Mar-07 23:35

I found the error:

Frame A is a Search Window whoch opens the Frame B, a Detail-Window.

If i search a customer and hit enter-key the customer will be opened into a new Tab of
Frame B ( B will be created if not already exists ) and A minimizes

If i close all Tabs from B, B minimizes and A appears(restore)

So i need a pointer from A to B and B to A.

At the destructor of B i test of A is still present, if yes, his pointer to B will be NULL, because
B is beeing destroyed and A does no more have a relation to B.

The test, if A is still present, was not good enough, i called the Frame A, then his View ( which was already deleted ) and modified his pointer to B ( to NULL )

In that way i get the "modified after freed"

James R. Twine,prasad_som : Thanks nevertheless Smile | :)

About System

Tran Ngoc Minh13-Mar-07 2:34

Tran Ngoc Minh

13-Mar-07 2:34

Hi Everyone!
I have two problems want question everyone :
First ,I want to set a Picture(has
tail :.gif , .bmp ,...) to DeskTop .
Second ,I am programming in Win32(VC++6.0),i want to
create a popup menu in Listbox .
Please help me !
Thanks

Re: About System

Hamid_RT13-Mar-07 3:05

Hamid_RT

13-Mar-07 3:05

For second question see WM_CONTEXTMENU and first question you need to path on the registry

WhiteSky

Visual Studio 2005 Installation Errors - How to FIx them [modified]

NiceNaidu13-Mar-07 2:16

NiceNaidu

13-Mar-07 2:16

Hi Friends,
While i was trying to install VS2005, I got so many errors. especially errors related to "cab" files.
Here i just want to share how i fixed them.
Hoping this will be helpful to the people,who come across this kind of errors.

Steps :
______

1)Remove the network cable from your machine.
2)Uninstall the "Anti-Virus" program.I don't know how it will effect the installation.
3)It is preferred to copy the CD contents to a sample folder in the C drive and then install the setup.
4)Whenever you get "cab" file corruption error.Try to copy the file to some other location and again try to replace the original file with the copied file.(though the two files are same). and then click on retry..(It worked for me.)

I am not hundred percent sure,whether all these things are going to work.But it worked for me.

Comments welcome.

Thanks. Smile | :)

-- modified at 9:34 Tuesday 13th March, 2007

Appu..
"My blood group is not B+.But I have it my blood"

Images in ListControl

gan_esh13-Mar-07 2:04

gan_esh

13-Mar-07 2:04

Hi Everyone,

In my application I want the images like (BMP,JPEG..) to be dragged from tree control and dropped into the Listcontrol. I used the FiletreeCtrl sample for tree control could anyone of you help me how to get the images of the files to be dragged and droped into the listcontrol.

Looking forward your reply

with regards,

ganesh

Re: Images in ListControl

Hamid_RT13-Mar-07 2:19

Hamid_RT

13-Mar-07 2:19

Use of LVN_BEGINDRAG

WhiteSky

which of the following to look at?

ShaluMalu13-Mar-07 1:54

ShaluMalu

13-Mar-07 1:54

Hi everybody!

I want to transfer the files saved in a particular time interval.... for that should i find the last accessed time or last modified time of the file?
Which of these has to be found if it is a folder?

Thanks!

Re: which of the following to look at?

James R. Twine13-Mar-07 2:00

James R. Twine

13-Mar-07 2:00

Since you are looking for files that have been saved (read: written to the disk, thus modified), I would look for the last modified date/time, not the last accessed date/time.

Peace!

How I can add elements in multiple columns in a OWNER Drawn List box?

Sameer_Thakur13-Mar-07 1:49

Sameer_Thakur

13-Mar-07 1:49

Hi..

Any Suggestion?

Thanks

Sameer Thakur

Re: How I can add elements in multiple columns in a OWNER Drawn List box?

Hamid_RT13-Mar-07 2:12

Hamid_RT

13-Mar-07 2:12

Why you dont use of CListCtrl instead ListBox its flexible

WhiteSky

Re: How I can add elements in multiple columns in a OWNER Drawn List box?

Sameer_Thakur13-Mar-07 3:23

Sameer_Thakur

13-Mar-07 3:23

BCoz I have already used List box in my application and I am displaying images and string in it ;in a single column, but now I want to display the contents in multiple columns.

Thanks

Sameer Thakur

Re: How I can add elements in multiple columns in a OWNER Drawn List box?

Hamid_RT13-Mar-07 3:34

Hamid_RT

13-Mar-07 3:34

I said CListCtrl not CListBox

WhiteSky

Re: How I can add elements in multiple columns in a OWNER Drawn List box?

Sameer_Thakur13-Mar-07 3:51

Sameer_Thakur

13-Mar-07 3:51

Ya got it.
But What I am trying to say is....

I have already developed an application with OWNER DRAWN List Box. But the concern is the elements are displayed in a single column....one below the other.
Now the list contents are large in number, SO I want to minimize users efforts to scroll the list box by clicking on scroll arrows.

I want to load the list box contents in multiple columns so that he can see more than one contents in a single row and will not have to scroll much.

Thanks

Sameer Thakur

Re: How I can add elements in multiple columns in a OWNER Drawn List box?

Hamid_RT13-Mar-07 3:57

Hamid_RT

13-Mar-07 3:57

See Multiple Column List Box Custom Control[^]

WhiteSky

Re: How I can add elements in multiple columns in a OWNER Drawn List box?

Hamid_RT13-Mar-07 18:22

Hamid_RT

13-Mar-07 18:22

Is your problem solving? Big Grin | :-D

WhiteSky

Re: How I can add elements in multiple columns in a OWNER Drawn List box?

Sameer_Thakur14-Mar-07 2:06

Sameer_Thakur

14-Mar-07 2:06

Sameer Thakur

Re: How I can add elements in multiple columns in a OWNER Drawn List box?

Hamid_RT14-Mar-07 3:18

Hamid_RT

14-Mar-07 3:18

Why did you see that article not helpful

WhiteSky

I don't have the CTime for this!

rw10413-Mar-07 1:33

rw104

13-Mar-07 1:33

Greetings,

I was led to believe that SYSTEMTIME is a UTC time.

Why then when I set my clock to the timezone (Baku GMT +04:00) with dayliight savings on (I have advanced to July 2007 so DST is in effect) i call CTime::GetAsSystemTime() I get the local time in the wHour, wMinute etc... structure members?

SYSTEMTIME myTime;
CTime temp= CTime::GetCurrentTime();
temp.GetAsSystemTime(myTime);

Eventually all i want to do is given the Local Date/Time get the Local Date/Time @GMT Start of Day

e.g. for Local Time 12th July 2007 3:00am (GMT +4:00 DST), the GMT day actually started on 11th July 19.00am (GMT +4:00 DST).

Re: I don't have the CTime for this!

rw10413-Mar-07 1:42

rw104

13-Mar-07 1:42

Sorry regarding the e.g.

e.g. for Local Time 12th July 2007 3:00am (GMT +4:00 DST), the GMT day actually started on 11th July 05.00am (GMT +4:00 DST).

Appending data to a file

Programm3r13-Mar-07 1:27

Programm3r

13-Mar-07 1:27

Hi all,

I'm trying to append data to a file. I have tried the following without success:

HANDLE hFile;
char buffer[BUFSIZE];
DWORD dwBytesWritten;
DWORD nNumberOfBytesToWrite;
BOOL fSuccess;

hFile = CreateFile(TEX("C:\\testing.txt"),
		GENERIC_WRITE,
		0,
		NULL,
		OPEN_ALWAYS,
		FILE_ATTRIBUTE_NORMAL,
		NULL);

sprintf(buffer,"%s",tcpClass.transRequest);//transRequest contains the data (characters)

fSuccess = WriteFile(hFile,
	buffer,
	strlen(buffer)+1,
	&dwBytesWritten,
	NULL);

The problem is that the data doesn't append to the end of the file.
for example:
example1
example2
example3
...

Can anyone please help me.
Many Thanx
Regards,

The only programmers that are better than C programmers are those who code in 1's and 0's..... Smile | :)

Programm3r
My Blog: ^_^

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