Qt execute multiple get with QNetworkAccessManager

Qt execute multiple get with QNetworkAccessManager

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Qt execute multiple get with QNetworkAccessManager
Tag : cpp , By : KT.
Date : January 02 2021, 06:48 AM

will help you I have tested your code and I have not noticed that the GUI is blocked, in addition to using signals and slots you should not have that problem. However I see that you are creating dynamic memory unnecessarily, in the following code I connect the QNetworkReply to a slot, filter through the QUrl and delete the QNetworkReply:
private slots:
    void on_pushButton_clicked();
    void on_pushButton_2_clicked();
    void onReplyfinished();

    Ui::MainWindow *ui;
    QNetworkAccessManager *manager;
MainWindow::MainWindow(QWidget *parent) :
    ui(new Ui::MainWindow)
    manager = new QNetworkAccessManager(this);

    delete ui;

void MainWindow::on_pushButton_clicked()
   QNetworkReply *reply = manager->get(QNetworkRequest{QUrl{"http://www.link.com/path/"}});
   connect(reply, &QNetworkReply::finished, this, &MainWindow::onReplyfinished);

void MainWindow::on_pushButton_2_clicked()
   QNetworkReply *reply = manager->get(QNetworkRequest{QUrl{"https://ergast.com/api/f1/2008/5.json"}});
   connect(reply, &QNetworkReply::finished, this, &MainWindow::onReplyfinished);

void MainWindow::onReplyfinished()
    QNetworkReply *reply = qobject_cast<QNetworkReply*>(sender());
    if(reply->url() == QUrl{"http://www.link.com/path/"}){
        ui->lineEdit->setText(reply->error() ? "error": reply->readAll());
    else if (reply->url() == QUrl{"https://ergast.com/api/f1/2008/5.json"}){
        ui->lineEdit_2->setText(reply->error() ? "error": reply->readAll());

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Qt QNetworkAccessManager and multiple QNetworkReply

Tag : qt , By : krs
Date : March 29 2020, 07:55 AM
will be helpful for those in need You can create a RequestSender class whose role is looking after requests.
Each RequestSender object will handle one unique request. While creating the QNetworkRequest that will be sent, the RequestSender will "tag" its own request with the originatingObject attribute. This attribute indicates which object sent the request. When a RequestSender object receives a reply, it will look if it is the sender of the request via the originatingObject attribute. For further informations about originatingObject, you can refer to the documentation here : http://qt-project.org/doc/qt-4.8/qnetworkrequest.html#originatingObject
class RequestSender {
        void createRequest(/* Request parameters */);

    public slots:
        void endRequest(QNetworkReply* replay);
RequestSender::RequestSender() {
    connect(nam, SIGNAL(finished(QNetworkReply*)), this, SLOT(endRequest(QNetworkReply*)));

RequestSender::~RequestSender() {
    disconnect(nam, SIGNAL(finished(QNetworkReply*)), this, SLOT(endRequest(QNetworkReply*)));

void RequestSender::createRequest(/* Request parameters */) {
    QNetworkRequest * myRequest = 0;

    // Build myRequest with the request parameters



void RequestSender::endRequest(QNetworkReply* replay) {
    if (replay->request().originatingObject() != this) {
        // That's not the request sent by the object -> stop the method here !

    // Treatments on replay

Qt QNetworkAccessManager & multiple QNetworkReplay

Tag : qt , By : Arun Thomas
Date : March 29 2020, 07:55 AM
Any of those help maybe you can do something like this: having an enum of the different methods
enum GetMethod
QHash<QNetworkReply*, GetMethod> hash;

QNetworkReply *reply1 = nam->post(requestUserId, data);
hash[reply1] = GetMethod::getUserId;

QNetworkReply *reply2 = nam->post(requestUserDetails, data);
hash[reply2] = GetMethod::getUserDetails;

connect(nam, SIGNAL(finished(QNetworkReply*)), this, SLOT(finished(QNetworkReply*)));
void MainWindow::finished(QNetworkReply *reply)
    case GetMethod::getUserId:
    case GetMethod::getUserDetails:


error: no matching function for call to 'QNetworkAccessManager::QNetworkAccessManager(Networking* const)'

Tag : cpp , By : Eniac
Date : March 29 2020, 07:55 AM
I wish did fix the issue. This is my files. I have some problems with that. , Add Q_OBJECT macro to your class without ;
class Networking : public QObject
    void getNetReply();

using QNetworkAccessManager GET multiple times

Tag : cpp , By : user161380
Date : March 29 2020, 07:55 AM
this one helps. I am writing an application to request a web page at equal intervals in order to get any changes in it (to check whether new data is received). here how i did it. , I see following problems:

trying to send file using QNetworkAccessManager get() but not QNetworkAccessManager post()

Tag : cpp , By : nhuser
Date : March 29 2020, 07:55 AM
To fix the issue you can do I am a newbie, I am trying to send a .xml file to server using Qt4.8. My restriction is , I am told to use QNetworkAccessManager->get() only. Although QNetworkAccessManager->post is available but I can't use it as per instruction given to me. So, write following code:- , I figure it out, you have to add data as query. code will like this:-
bool PIS::sendPISData(QString xmlFile,QString IP)
    QFile xmlfyle(xmlFile);
        #ifdef DEBUG
        qDebug("Can not open file device.");

    QString content = (QString)xmlfyle.readAll();
    #ifdef DEBUG
    qDebug()<<"content :::  "<<content;
    QNetworkAccessManager mgr;
    QEventLoop eventLoop;
    QUrl url(QString("http://"+IP+"/Smart_Coach_Service/data_interchange/senddata"));
    url.addQueryItem("xml_data", content);
    QNetworkReply *replyn = mgr.get(reqpn);
    connect(replyn, SIGNAL(finished()), &eventLoop, SLOT(quit()));
    return true;
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