Qt实现生成指定范围内随机数与随机字符串

#include <QTime> 
void generateRandomNumber()
{
    qsrand(QTime(0,0,0).msecsTo(QTime::currentTime()));
    for(int i=0; i<3; i++)
    {
        int test =qrand()%256;
        QTest::qSleep(1);
        qDebug()<<test;
    }
}

int generateRandomNumber(int min,int max)
{
    qsrand(QTime(0,0,0).msecsTo(QTime::currentTime()));
    int num = qrand()%(max-min)+min;
    qDebug()<<num;
    return num;
}

int getRandom(int min,int max)
{
    QList<int> list;
    int i,j;
    bool res = true;
    qsrand(QTime(0, 0, 0).msecsTo(QTime::currentTime()));
    for (int i=0; i<10; i++) {
        int num = qrand()%(max-min)+min;
        list.append(num);
        while(res)
        {
            for(j=0;j<i;j++)
            {
                if(list[i]==list[j])
                    break;
            }
            if(j<i)
            {
                list[i] = qrand()%(max-min)+min;
            }
            if(j==i)
                res=!res;
        }
    }
}

QString getRandomString(int length)
{
    qsrand(QDateTime::currentMSecsSinceEpoch());
    const char ch[] = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ";
    int size = sizeof(ch);
    char* str = new char[length + 1];
    int num = 0;
    for (int i = 0; i < length; ++i)
    {
        num = rand() % (size - 1);
        str[i] = ch[num];
    }
    QString res(str);
    return res;
}