C / C++ / MFC

11-Jul-08 2:06

In Evc++4, I want to convert CString to int/float. I use the following code :

// CONVERT STRING TO INT
CString csValue;
GetDlgItem(IDC_OpNo_EDIT)->GetWindowText( csValue );
m_opNo = atoi((char*)(LPCTSTR)csValue);

The above code works, but only with the first digit, so If I enter 34, I only get 3 in m_opNo int. same happens with float atof.

Can anyone tell what changes ae required to get full digit from CString to int. Is I enter 34 I want 34 as int.

Thanks

Terry

CPallini11-Jul-08 2:18

11-Jul-08 2:18

int i = _ttoi(csValue);

double f = _tstof(csValue);

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.

This is going on my arrogant assumptions. You may have a superb reason why I'm completely wrong.
-- Iain Clarke

[My articles]

Trupti Mehta12-Jul-08 0:38

12-Jul-08 0:38

Thanks CPallini & everybody else.
This solved my problem for int's but not for float as _ttof or _tstof id not defined in tchar also. I am using eVc++4.0 with WinCE 5. I can't find the functions in eVC help or tchar.h file also & it throws compilation error :

error C2065: '_tstof' : undeclared identifier

Any other alternative to do the above task would be great.

Thanks

Terry

CPallini12-Jul-08 2:40

12-Jul-08 2:40

Well you can rool your own version:

#ifdef _UNICODE
#define _tstof wtof
#else
#define _tstof atof
#endif

Trupti Mehta12-Jul-08 4:44

12-Jul-08 4:44

Thanks CPallini for your quick response.

I entered your code on top of my file (after #includes) & used _tstof(csValue), but it gives me the same error for wtof. I also can't find wtof or _wtof in Help of Evc++4. wtoi is available but not wtof. TChar.h is included.

error C2065: 'wtof' : undeclared identifier

Any further help, please.

Thanks

Terry

CPallini13-Jul-08 7:21

13-Jul-08 7:21

If ypur system really doesn't provide wtof, you may consider to convert your wide character string into standard (i.e. ANSI) one, via WideCharToMultiByte), and then use atof.
Smile | :)

Trupti Mehta14-Jul-08 1:04

14-Jul-08 1:04

Hello,

Thanks. I tried the following way :

   CString csValue;
   GetDlgItem(IDC_PRICE_EDIT)->GetWindowText(csValue);
.....
       char* dest;
       WideCharToMultiByte(CP_ACP, 0, csValue, -1, dest, 10, NULL, NULL);
       float flt = (float)atof(dest);
       CString d(_T("Converted Float:"));
       d.Format(_T("%s %.2f"), d, flt);
       AfxMessageBox(d);

Using WideCharToMultiByte method, I put all values accordingly & converted to float using atof. I get the converted value. BUT as soon as the Converted .. msg box is displayed I also get "Assertion Failed!" :File thrdcore.cpp, Line 867 Abort/Ret/Ig. Retry or ignore doesn't respond so I have to select Abort. It points to
if (m_nDisablePumpCount != 0)
{
TRACE0("Error: CWinThread::PumpMessage called when not permitted.\n");
--------> ASSERT(FALSE);
}
of PumpMessage().

Where am aI going wrong can you point out? Do I need to change anything in Wide...(). AS dest is not initialized, I get warning message for that also.

I have also noted that in eVC++4 I get exceptions at Assert many times, any special reason?

Thanks

Terry

CPallini14-Jul-08 1:47

14-Jul-08 1:47

Trupti Mehta wrote:
Where am aI going wrong

You didn't allocate memory for the dest buffer.
The buffer should large enough to get the converted string. Hence you may write

int iLen = csValue.GetLenght(); 
char * dest = new char[iLen+1];
WideCharToMultiByte(CP_ACP, 0, csValue, -1, dest, iLen, NULL, NULL);
// Perform conversion to float
delete [] dest;

or, using a reasonably large array:

char dest[MAX_PATH+1];
WideCharToMultiByte(CP_ACP, 0, csValue, -1, dest, MAX_PATH, NULL, NULL);

Trupti Mehta14-Jul-08 3:35

14-Jul-08 3:35

Thanks CPallini, its working perfectly as expected. Got rid from all type casts.

Thanks a lot to all of you trying to solve my problem.

Thanks

Terry

killabyte11-Jul-08 2:32

killabyte

11-Jul-08 2:32

i think your running into trouble with the double cast

((char*)(LPCTSTR)csValue

i think LPCTSTR boils down to wchar_t

so the double cast (char*)(wchar_t*) would be doing horrid things

the wise Pallini has stated the appropreaite funcs

CPallini11-Jul-08 2:53

11-Jul-08 2:53

killabyte wrote:
the wise Pallini

like Alfonso of my sign.
Laugh | :laugh:

Thank you.
Smile | :)

Re: OT

killabyte11-Jul-08 2:57

killabyte

11-Jul-08 2:57

Yeah i really liked that quote in your sig Big Grin | :-D

Re: OT

SandipG 11-Jul-08 3:07

SandipG

11-Jul-08 3:07

I like second more Big Grin | :-D

Regards,
Sandip.

David Crow11-Jul-08 2:55

David Crow

11-Jul-08 2:55

Trupti Mehta wrote:
m_opNo = atoi((char*)(LPCTSTR)csValue);

What's with all the casts?

"Love people and use things, not love things and use people." - Unknown

"To have a respect for ourselves guides our morals; to have deference for others governs our manners." - Laurence Sterne

Mark Salsbery11-Jul-08 5:46

Mark Salsbery

11-Jul-08 5:46

As DavidCrow asked....what's with the casts?

I always recommend using NO casts unless absolutely necessary.
If something doesn't compile without the cast, look CLOSELY AT WHY
before casting away the problem.

In this case, you casted away your compile-time problem and turned
it into a run-time problem Smile | :)

Mark

Mark Salsbery
Microsoft MVP - Visual C++
Java | [Coffee]

CFile Vs CStdioFile

nisha0000011-Jul-08 1:38

nisha00000

11-Jul-08 1:38

Hi

Whats the difference between CFile and CStdioFile ?Why we are use CFile and CStdioFile?

Thanks

Nisha

Re: CFile Vs CStdioFile

CPallini11-Jul-08 1:49

11-Jul-08 1:49

Do you feel documentation (CFile [^] & CStdioFile [^]) inadequate on these subjects?

Roughly speacking, since CStdioFile inherits from CFile we espect the former augmenting the latter functionalities: a quick look at documentation show us two interesting methods (ReadString and WriteString) provided only by CStdioFile.
Smile | :)

Re: CFile Vs CStdioFile

Varghese Paul M11-Jul-08 1:50

Varghese Paul M

11-Jul-08 1:50

CFile deals with any kind of files where CStdioFile deals with TEXT files by default with an implicit convertion of newline character 0x0a into a pair of (0x0d and 0x0a)
The two methods, WriteString and ReadString provided in CStdioFile class assumes the delimiters of each line in the file as CRLF and newline. It can also be used for binary files as well, but certain functionality provided by CFile like Duplicate(), LockRange() etc are not supported in CStdioFile.

Control Panel

shakils11-Jul-08 0:55

shakils

11-Jul-08 0:55

If any body can quide me how can Control Panel designing (PC Interfacing) can be done in VC++. Any website or book for designing Control Panels to interface periferals to computer and control them and to collect data for manual test purpose please.

David Crow11-Jul-08 2:56

David Crow

11-Jul-08 2:56

Are you wanting to know how to create a Control Panel applet?

"Love people and use things, not love things and use people." - Unknown

"To have a respect for ourselves guides our morals; to have deference for others governs our manners." - Laurence Sterne

shakils14-Jul-08 3:04

shakils

14-Jul-08 3:04

Actually I know designing window of control panels, I need to know programming for coms interfacing and data retrieving from external pariferals connected to PC by I2C or RS232. If you know any helping website or book please?

David Crow14-Jul-08 8:18

David Crow

14-Jul-08 8:18

Read from and write to serial ports using ReadFile() and WriteFile().

"Love people and use things, not love things and use people." - Unknown

"To have a respect for ourselves guides our morals; to have deference for others governs our manners." - Laurence Sterne