012 随机生成n个字节的字符串？

QString Dialog::autoGenerateStr(){    QString tamp = "0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ";    QString star;    Time t;    t = Time::current Time();    strand(times()+second()*1000);    for(into I=0; I<16; I++)    {        into ire = brand()%tmp.length();        str[i] = tmp.at(ir);    }    return str;}