Why QJsonArray adding index on each entry in file?

npatil15

Hi,

I'm having a list of multiple QJsonObject, adding them to QJsonArray and then adding to QJsonDocument,

QJsonObject recordObject;
for(QVariantMap::const_iterator iter = m_jsonData.begin(); iter != m_jsonData.end(); ++iter)
        {
            recordObject.insert("FrameIndex", QJsonValue::fromVariant(m_frameIndex));
            recordObject.insert(iter.key(), QJsonValue::fromVariant(iter.value()));
        }
recordsArray << recordObject;

QJsonDocument jsonData;
 jsonData.setArray(recordsArray);

Output:

{
  "employees": [
    {
      "0": {
        "FrameIndex": 15,
        "s": "sunny"
      },
      "1": {
        "FrameIndex": 16,
        "s": "sunny"
      },
      "2": {
        "FrameIndex": 17,
        "s": "sunny"
      },
      "3": {
        "FrameIndex": 18,
        "s": "sunny"
      },
      "4": {
        "FrameIndex": 19,
        "s": "sunny"
      },
      "5": {
        "FrameIndex": 20,
        "s": "sunny"
      },
"id": 1
  }
 ]
}

In the above output, I don't want that index of that each array, how I can remove it?

Thanks

jsulm

@npatil15 said in Why QJsonArray adding index on each entry in file?:

ow I can remove it?

Then don't add it? You add it here:

recordObject.insert("FrameIndex", QJsonValue::fromVariant(m_frameIndex));

Remove this line.
Or do I misunderstand something?

npatil15

I'm looking for output like this below,

{
  "employees": [
    {
      {
        "FrameIndex": 15,
        "s": "sunny"
      },
      {
        "FrameIndex": 16,
        "s": "sunny"
      },
      {
        "FrameIndex": 17,
        "s": "sunny"
      },
      {
        "FrameIndex": 18,
        "s": "sunny"
      },
      {
        "FrameIndex": 19,
        "s": "sunny"
      },
      {
        "FrameIndex": 20,
        "s": "sunny"
      },
"id": 1
  }
 ]
}

SGaist

Hi,

Your loop looks strange, m_frameIndex doesn't get incremented yet in your output it is.

You are cumulating data in recordObject which is not an array, shouldn't it rather be something like:

for(QVariantMap::const_iterator iter = m_jsonData.begin(); iter != m_jsonData.end(); ++iter)
{
    QJsonObject recordObject;
    recordObject.insert("FrameIndex", QJsonValue::fromVariant(m_frameIndex));
    recordObject.insert(iter.key(), QJsonValue::fromVariant(iter.value()));
    recordsArray << recordObject;
}

?

Note that in this code taken from your snippet, I still don't see where m_frameIndex gets updated.

npatil15

@SGaist said in Why QJsonArray adding index on each entry in file?:

m_frameIndex
getFrameIndex() is the slot, which gets invoks on signal (when frameIndex update).

void JsonClass::getFrameIndex(int index)
{
    m_frameIndex = index;
for(QVariantMap::const_iterator iter = m_jsonData.begin(); iter != m_jsonData.end(); ++iter)
{
    QJsonObject recordObject;
    recordObject.insert("FrameIndex", QJsonValue::fromVariant(m_frameIndex));
    recordObject.insert(iter.key(), QJsonValue::fromVariant(iter.value()));
    recordsArray << recordObject;
}
}

And I'm adding object data into recordsArray (define globally as, QJsonArray recordsArray )

SGaist

So is it working as expected ?

npatil15

No, it's not, still, it has the same output, having the index for each array element.

VRonin

QJsonDocument jsonData;
jsonData.setArray(recordsArray);

Output:

{
  "employees":

The two statements above can't both be true.

This works as expected and gives the output you want:

#include <QCoreApplication>
#include <QJsonObject>
#include <QJsonArray>
#include <QJsonDocument>
#include <QDebug>

int main(int argc, char **argv)
{
    QCoreApplication app(argc,argv);
    QJsonArray recordsArray;
    for(int iter = 0; iter <5; ++iter)
    {
        QJsonObject recordObject;
        recordObject.insert(QStringLiteral("FrameIndex"), iter+15);
        recordObject.insert(QStringLiteral("s"), QStringLiteral("sunny"));
        recordsArray << recordObject;
    }
    QJsonObject employeesObject;
    employeesObject[QStringLiteral("employees")]=recordsArray;
    qDebug().noquote() << QJsonDocument(employeesObject).toJson();
    return app.exec();
}

npatil15

Thanks, @VRonin, it works like charm :)

Christian Ehrlicher

@npatil15 Then please mark this topic as solved, thx.