Read Json from https in qt - c++

Question

I wrote this code on qt, but when i run this project, My output is "Error".
How can solve my problem?
For example in this code I add a address in url, and I want read Json from this url, and show some info.
MainWindow::MainWindow(QWidget *parent) :
QMainWindow(parent),
ui(new Ui::MainWindow)
{
ui->setupUi(this);
QNetworkAccessManager* nam = new QNetworkAccessManager(this);
QString test = "ar";
QString test2 = "Hello World";
QObject::connect(nam, SIGNAL(finished(QNetworkReply*)),
this, SLOT(onResult(QNetworkReply*)));
QUrl url("https://translate.yandex.net/api/v1.5/tr.json/translate?key=trnsl.1.1.20180627T161429Z.7e64c91dd2016a6c.9901da9a44bc324388a2460776ab55b2d72b4c5a&lang=" + test + "&text=" + test2);
QNetworkReply* reply = nam->get(QNetworkRequest(url));
}
void MainWindow::onResult(QNetworkReply *reply)
{
if(reply->error() == QNetworkReply::NoError) {
QStringList propertyNames;
QStringList propertyKeys;
QString strReply = (QString)reply->readAll();
qDebug() << strReply;
QJsonDocument jsonResponse = QJsonDocument::fromJson(strReply.toUtf8());
QJsonObject jsonObject = jsonResponse.object();
QJsonArray jsonArray = jsonObject["status"].toArray();
qDebug() << jsonObject["status"].toString();
foreach (const QJsonValue & value, jsonArray)
{
QJsonObject obj = value.toObject();
qDebug() << value.toString();
}
} else {
qDebug() << "ERROR";
}
delete reply;
}

Answer 1

To add key-values ​​to the url you must use QUrlQuery as shown below:
MainWindow::MainWindow(QWidget *parent) :
QMainWindow(parent),
ui(new Ui::MainWindow)
{
ui->setupUi(this);
nam = new QNetworkAccessManager(this);
connect(nam, &QNetworkAccessManager::finished, this, &MainWindow::onResult);
QString lang = "ar";
QString text = "Hello World";
QString key = "trnsl.1.1.20180627T161429Z.7e64c91dd2016a6c.9901da9a44bc324388a2460776ab55b2d72b4c5a";
QUrlQuery query;
query.addQueryItem("key", key);
query.addQueryItem("lang", lang);
query.addQueryItem("text", text);
QUrl url("https://translate.yandex.net/api/v1.5/tr.json/translate");
url.setQuery(query);
qDebug()<< "url: "<< url.toString(QUrl::FullyEncoded);
nam->get(QNetworkRequest(url));
}
void MainWindow::onResult(QNetworkReply *reply){
if(reply->error() == QNetworkReply::NoError){
QByteArray result = reply->readAll();
QJsonDocument jsonResponse = QJsonDocument::fromJson(result);
QJsonObject obj = jsonResponse.object();
qDebug()<<"code: " << obj["code"].toInt();
qDebug()<<"lang: " << obj["lang"].toString();
QJsonArray array = obj["text"].toArray();
for(const QJsonValue & value : array) {
qDebug()<< "text: " <<value.toString();
}
}
else
qDebug() << "ERROR";
reply->deleteLater();
}
Output:
url: "https://translate.yandex.net/api/v1.5/tr.json/translate?key=trnsl.1.1.20180627T161429Z.7e64c91dd2016a6c.9901da9a44bc324388a2460776ab55b2d72b4c5a&lang=ar&text=Hello%20World"
code: 200
lang: "en-ar"
text: "مرحبا العالم"
If the url generated is revised, it differs from the concatenation:
Concatenation:
...&text=Hello World
Encoded:
...&text=Hello%20World