直接上货，不墨迹！
QString str_QString;
std::string str_string;
char *_pChar;
int a;
1、
str_QString = str_string.c_str();
str_QString = QString(_pChar);
str_QString = QString::number(a);
2、
str_string = str_QString.toStdString;
str_string = str_QString.local8Bit();
str_string = _pChar;
3、
_pChar = str_string.c_str();
_pChar = (const char *)str_QString.local8Bit();
_pChar = (char *)std_string;
4、
a = str_QString.toint();
a = (int)_pChar;
a = atoi(str_string.c_str());
