Qt request dynamic XML from Web

Question

I learn Qt and I want to download a XML file from the Internet. The QUrl is depending on further values value1 and value2; example:

http://www.example.org/path/the_xml_file.xml?value1=1&value2=2

Here I set the QString destination_XML_URL

void AClass::setUrlString(quint32 t_value1, quint32 t_value2) {
    destination_XML_URL = QString("http://www.anyweb.com/path/the_xml_file.xml?value1=%1&value2=%2").arg(t_value1).arg(t_value2);
}

Then I request that location with a QUrl in a method:

QNetworkAccessManager url_network_access_manager;
//..;
setTarget(12, 34);  
QUrl xml_Url(destination_XML_URL);
QNetworkRequest request(xml_Url);
QNetworkReply url_network_reply = url_network_access_manager.get(request);

Finally connecting the connect:

connect(&url_network_access_manager, SIGNAL(finished(QNetworkReply*)), this, SLOT(slot_disconnect2Net(QNetworkReply*)));

Then the slot, after retrieving the xml file from web:

void AClass::slot_disconnect2Net(QNetworkReply *data) {
    qint64 t_size1 = data->size();
    int error_code = data->error();
    switch(error_code) {
        case 0:
            transform_Raw_2_XML(data);
            break;
        case 3:
            break;
        case 301:
            break;  
        default:
            QMessageBox::critical(this, "AClass::disconnect2Net()", QString("Connection error %1:\n %2").arg(error_code).arg(data->errorString()), QMessageBox::Ok);
    }
}

But I get error_code 3:

http://doc.qt.io/qt-4.8/qnetworkreply.html#NetworkError-enum

"QNetworkReply::HostNotFoundError = 3 : the remote host name was not found (invalid hostname)"

Any ideas?

Answer 1

Is it possible, that your connection is behind a proxy?