C / C++ / MFC Discussion Boards

CPallini19-May-08 0:08

19-May-08 0:08

I strogly suggest you following the toxcct's article approach.

Anyway, using the global variable approach is simple:
(1) declare, in a common included header file, the variable as extern.
(2) define the variable only in one source file.

For instance, in your main header file (let's assume it is YourApp.h)

extern CString g_MyString; // declaration as extern

and in the main source file, and only there (let's assume again it is YourApp.cpp)

CString g_MyString; // definition

Now you can use g_MyString in any *.cpp file that includes the main header file (i.e. YourApp.h).

You may find a working example of global variable in your sources, since Visual Studio generates code for the global variable theApp.
Smile | :)

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Re: datatransfer

Nelek19-May-08 7:37

Nelek

19-May-08 7:37

mmm, nice shortcut.

I had it defined in only one cpp as you said, but I was using "extern type var" everywhere I wanted to use it Blush | :O

Thanks for the trick Roll eyes | :rolleyes:

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Re: datatransfer

Mohanraj D19-May-08 20:18

Mohanraj D

19-May-08 20:18

ok,thank u

Raja

Re: datatransfer

Mohanraj D19-May-08 20:19

Mohanraj D

19-May-08 20:19

ok thank u

Raja

Re: datatransfer

Rajesh R Subramanian19-May-08 1:04

Rajesh R Subramanian

19-May-08 1:04

Another way would be to store your application related information in the registry or in an ini file.

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.·´¯`·->Rajesh<-·´¯`·.
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Re: datatransfer

David Crow19-May-08 4:00

David Crow

19-May-08 4:00

Mohanraj D wrote:
error C2065: 'str' : undeclared identifier

The error message tells it all. You have failed to declare str. Should be:

CString str = "data;

But that does nothing to solve your original problem. Before calling DoModal(), you need to populate some variable that belongs to your datatransfer class (e.g., array, list, vector). You can either do this by accessing the variable directly, or implement some sort of "setter" method. Then in the OnInitDiaog() method of datatransfer, populate the listbox with the data.

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Re: datatransfer

Hamid_RT19-May-08 1:34

Hamid_RT

19-May-08 1:34

You can use like this code(If we suppose first dialog is CMain) on the target:
CMain* m_Main=(CMain*)GetParent();
m_main->m_Litsbox

problem with fwrite

Cadimi18-May-08 22:50

Cadimi

18-May-08 22:50

I wrote a short code to write the status of my program to a file, but when debug in that code, I realize that fwrite function still increase its file pointer but when I read that file by fread function, I can't read that value. This is my code:

// TODO: Add your control notification handler code here
//write config file
FILE *fout = fopen( "config.pcm", "wb" );

if ( fout )
{
//write the time of power function
fwrite( &m_uTime, sizeof( int ), 1, fout );

unsigned long temp;
//write tasks
//number of day task
temp = m_alltasks.size();
fwrite( &temp, sizeof( long ), 1, fout );

for ( int i = 0; i < m_alltasks.size(); i++ )
{
//date
fwrite( &m_alltasks[i].date, sizeof( MYDATE ), 1, fout );

//number of notes in that day
temp = m_alltasks[i].tasks.size();
fwrite( &temp, sizeof( long ), 1, fout );

//notes
for ( int j = 0; j < m_alltasks[i].tasks.size(); j++ )
{
fwrite( &m_alltasks[i].tasks[j], sizeof( TASK ), 1, fout );
}
}

//how many hotkeys have been defined
temp = m_hkArr.size();

fwrite( &temp, sizeof( long ), 1, fout );

//write the list of hotkeys

for ( int i = 0; i < temp; i++ )
fwrite( &m_hkArr[i], sizeof( HOTKEY ), 1, fout );

fclose( fout );
}
else
{
MessageBox( _T( "Can't write config file" ), _T( "Warning" ) );
OnCancel();
}

//unregister hotkeys
for ( int i = 0; i < m_hkArr.size(); i++ )
{
UnregisterHotKey( m_hWnd, m_hkArr[i].id );
GlobalDeleteAtom( m_hkArr[i].id );
}

OnCancel();

They all work except for the code I bolded ( file pointer still increase, but the file is not change )... Help me plz >.<...