Russian Qt Forum

C++ (Qt)
const char *ss = qPrintable ( str );
char* ss = str.toAsii().data();

C++ (Qt)
const char *ss = qPrintable ( str );
char* ss = str.toAsii().data();

C++ (Qt)
#define qPrintable(string) (string).toLocal8Bit().constData();
 

C++ (Qt)
const char *func()
{
    QString str = "......";
    return qPrintable( str );
}
 

C++ (Qt)
QString str("bla-bla");
 
const char *ptrStr = str.toLocal8Bit().constData();
 
//do something with ptrStr

C++ (Qt)
int main(int argc, char *argv[])
{
    QString aaaa = QString("aaaaaBBBB");
    const char *astr = qPrintable(aaaa);
    qDebug("%s",astr);
    return 0;
}

==305== Invalid read of size 1
==305==    at 0x694EE0E: QString::fromUtf8(char const*, int) (in /usr/lib/libQtCore.so.4.5.0)
==305==    by 0x6951622: QString::vsprintf(char const*, __va_list_tag*) (in /usr/lib/libQtCore.so.4.5.0)
==305==    by 0x68FEDC7: qDebug(char const*, ...) (in /usr/lib/libQtCore.so.4.5.0)
==305==    by 0x40E2E1: main (main.cpp:20)
==305==  Address 0xbd35a68 is 24 bytes inside a block of size 41 free'd
==305==    at 0x4C265AF: free (vg_replace_malloc.c:323)
==305==    by 0x40E2D2: main (main.cpp:19)
UUUUUUUUUUUUUUUUU

C++ (Qt)
const char *ptrStr;
{
     QByteArray tmp = str.toAscii();
     ptrStr = tmp.constData();
}
 

C++ (Qt)
const char *ptrStr;
{
     QByteArray tmp = str.toAscii();
     ptrStr = tmp.constData();
}
 
// Использование
char ch = ptrStr[ 20 ];
 

C++ (Qt)
const char *ptrStr = str.toAscii().constData()
 
// Использование
char ch = ptrStr[ 20 ];
 

C++ (Qt)
qWarning("%s", str.toAscii().constData());

C++ (Qt)
some_function(str.toAscii().constData());
....
 
void some_function(const char *str)
{
    //do something with str
}

C++ (Qt)
const char *data = 0;
 
{
    QByteArray arr;
    data = arr.constData();
}
 
//do something with data