qt5.8如何连接mysql

#include "mainwindow.h"
#include <QApplication>
#include <QtSql/QSqlDatabase>
#include <QStringList>
#include <QtSql/QSqlDatabase>
#include <QtSql/QSqlQuery>
#include <qDebug>
int main(int argc, char *argv[])
{
 QApplication a(argc, argv);
 MainWindow w;
 w.show();
 QStringList drivers = QSqlDatabase::drivers();
 qDebug() << drivers;
 QSqlDatabase dbconn;
 QSqlQuery query;
 dbconn = QSqlDatabase::addDatabase("QMYSQL");
 dbconn.setHostName("192.168.80.221");//主机名字
 dbconn.setDatabaseName("iacrms");//数据库名字
 dbconn.open("gdzt", "039.com");//用户名、密码，成功返回1
 query = (QSqlQuery)dbconn;
 query.exec("select * from tb_UserQQInfo");
 while(query.next())
 {
 int id = query.value(0).toInt();
 QString name = query.value(1).toString();
 qDebug() << QString::number(id) + " : "+ name;
 }
 return a.exec();
}