QUrl模块提供了解析和拼装URL的一些方法，可以支持urlencode编码的URL。

The QUrl class provides a convenient interface for working with URLs.

It can parse and construct URLs in both encoded and unencoded form. QUrl also has support for internationalized domain names (IDNs).

编程示例如下：

#include <QCoreApplication>
#include <QtCore>

int main(int argc, char *argv[])
{
    QCoreApplication a(argc, argv);
    auto url=QUrl("http://user:pass@www.exm.cn:9090/index.php?a=1");
    qDebug() << url.scheme();
    qDebug() << url.host();
    qDebug() << url.port();
    qDebug() << url.query();
    qDebug() << url.path();
    url.setHost("www.sina.com");
    url.setPort(80);
    qDebug() << url.toString();
    qDebug() << url.toDisplayString(QUrl::RemoveUserInfo);
    return a.exec();
}

参考资料：

http://qt-project.org/doc/qt-5/qurl.html