c++ - QJsonDocument 在 C++ 中列出或排列

Question

我已经尝试过这段代码并且有效，但我不明白如何获取 json 并使用 Qt 转换为数组或列表。 我的代码:

QEventLoop eventLoop;


QNetworkAccessManager mgr;
QObject::connect(&mgr, SIGNAL(finished(QNetworkReply*)), &eventLoop, SLOT(quit()));


QNetworkRequest req(QUrl(QString("http://myurljson.com/getjson")));

QNetworkReply *reply = mgr.get(req);
eventLoop.exec(); // blocks stack until "finished()" has been called

if (reply->error() == QNetworkReply::NoError) {

    QString strReply = (QString)reply->readAll();    

    qDebug() << "Response:" << strReply;

    QJsonDocument jsonResponse = QJsonDocument::fromJson(strReply.toUtf8());
    QJsonObject jsonObj = jsonResponse.object();

    qDebug() << "test:" << jsonObj["MCC_Dealer"].toString();
    qDebug() << "test1:" << jsonObj["MCC_User"].toString();

    delete reply;
}
else {
    //failure
    qDebug() << "Failure" <<reply->errorString();
    delete reply;
}

我的 json 获取(来自 url 的 3 条记录):

[{"MCC_Dealer":'test',"MCC_User":'test',"CurrentDealer":'test',"CurrentUser":'test'},{"MCC_Dealer":'test',"MCC_User":'test',"CurrentDealer":'test',"CurrentUser":'test'},{"MCC_Dealer":'test',"MCC_User":'test',"CurrentDealer":'test',"CurrentUser":'test'}]

我需要获取 json 并在列表或数组中设置。 我的目标是用 c++ 和 Qt 转换数组或列表中的 json 响应。 有什么想法吗？

谢谢

Answer 1

正如我在评论中提到的，您的 JSON 响应已经是一个数组，因此您无需创建额外的结构来存储您获得的数据。为了反序列化您的数据，您可以执行以下操作:

[..]
QJsonArray jsonArray = jsonResponse.array();

for (auto it = jsonArray.constBegin(); it != jsonArray.constEnd(); ++it)
{
    const QJsonValue &val = *it;

    // We expect that array contains objects like:
    // {"MCC_Dealer":'test',"MCC_User":'test',"CurrentDealer":'test',"CurrentUser":'test'}
    QJsonObject o = val.toObject();

    // Iterate over all sub-objects. They all have string values.
    for (auto oIt = o.constBegin(); oIt != o.constEnd(); ++oIt)
    {
        // "MCC_Dealer":'test'
        qDebug() << "Key:" << oIt.key() << ", Value:" << oIt.value().toString();
    }
}