Pfthb

I am developing a desktop application which receives frames in bytes format from a server. I have the imei of the device sending those frames inside the frames received.

I have tried to add to a long long variable with the corresponding left shift to each byte (56, 48, 40..., 0) but number is longer than 40 bits so it does not work.

I just want it to put on a text box so in QString format would be enough but I am not confident at all with C++ and I don't see how I can get it.

For example, this imei: 352353222952355 would be received in a frame like this: [0x00, 0x01, 0x40, 0x76, 0xA0, 0xB0, 0x85, 0xA3] which I have in my QByteArray. Each time I try to print that variable with qDebug(), I get the hex representation ("x00x...."). What I want to get is the number as I put on the first line in this paragraph.

How can I convert to its decimal representation in a QString?

EDIT:
I want to add some information related to the test I am running with the help of @Peter

This is what I get if I print the QByteArray:

qDebug() << imei;
"x00x01@vx98[xD7xAF"

In case I pass that imei (QByteArray) to your function, I get:
QString imeiStr;
imeiStr = ConvertToQString(imei);

qDebug() << imeiStr;
"u0000u0001@v?[u05EF"

If I debug the application and show both variables (imei and imeiStr) I see some differences:

imeiStr is shorter and also, from position 4, differs from the original.

quint8 source[8] = 0x00, 0x01, 0x40, 0x76, 0xA0, 0xB0, 0x85, 0xA3;
QByteArray imei;
for(int i = 0; i < 8; ++i)
 imei.append(source[i]);


qlonglong val = 0;
for(int i = 0; i < 8; ++i)
 val *= 256;
 val += (quint8)imei.at(i);

qDebug() << QString::number(val);

You can use stringstreams:

#include <sstream>

QString ConvertToQString(const QByteArray& array)

 std::stringstream ss;
 for (int i = 0; i < array.size(); ++i)
 ss << array[i];

 return QString::fromStdString(ss.str());