Qt中字符串之间的转换

//QString -> C++ string -> char *
str.ToStdString().data();    //先转换为C++的标准编码

//QString -> QByteArray
QString buf = "123456";
QByteArray a = buf.toUtf8();//中文
a = buf.toLocal8Bit(); //转换为本地编码  

//QByteArray -> char *
char *b = a.data()

//char * -> QString
char *p = "123"
QString c = QString(p);