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QByteArray class input to function - pass by reference or pass by value???

  • When passing a QByteArray variable to a function, is the variable pass by reference or pass by value?

    I have the following code in my program:

    // global variable
    QByteArray RX_Buffer;

    // In one of my function, I am passing RX_Buffer to a function
    bool ParseMessage (QByteArray data, QByteArray rx_data)
    // state machine processing to populate values to rx_data
    for(int i = 0; i < 10; i++)
    rx_data[i] = (quint8)i;
    bool cls_ElectricityMeter::ReadDemo()
    ParseMessage(TX_Buffer, RX_Buffer);
    return false;

    At the return point of ReadDemo function, RX_Buffer.data() does not contain the populated values from ParseMessage. Am I doing something wrong?

  • If you want to change your method parameter you should pass it by reference (i.e. with &). In your case implicitly shared copy created at method call and after first assign sharing breaks.

  • sorry but I do not quite understand . Can you provide a code snippet?

  • nevermind... i got it!!! thanks a bundle. I assumed classes were pass by reference by default for some reason.

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