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Thread: QDateTime to QString Hex to QByteArray - Problem (

  1. #1
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    Default QDateTime to QString Hex to QByteArray - Problem (

    ЗдравствуйтРµ, прошу прощения, что пиши по русски.
    Возникла проблема.
    ПреобразовыРаю QdateTime (unix) в Hex QString
    Qt Code:
    1. QString time = QString("%1").arg(QDateTime::currentDateTime().toTime_t(),0,16).toUpper();
    To copy to clipboard, switch view to plain text mode 
    Всё окей.
    После пытаюсь сделать
    Qt Code:
    1. QByteArray myHexArray = QByteArray::fromHex(time.toLatin1());
    To copy to clipboard, switch view to plain text mode 
    но выходит какая-то лажа.
    к примеру получил я HEX - 57640466
    Если я вручную ввожу его
    Qt Code:
    1. QByteArray myHexArray = QByteArray::fromHex("57640466");
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    То всё правильно происходит на выходе вижу
    Qt Code:
    1. 0x57 0x64 0x04 0x66
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    А если заместо значения подставляю time то на выходе получается hex обёрнутый ещё раз в hex
    Как так я не понимаю.
    Даже если со значениями всё ок, дальше почему-то
    если беру отдельно индекс 0 у myHexArray получаю не 0x57, а
    [0] = 0x05, [1] = 0x07
    Помогите пожалуйста )

  2. #2
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    Default Re: QDateTime to QString Hex to QByteArray - Problem (

    Courtesy of Google Translate
    Quote Originally Posted by f00rZik View Post
    Hello, I am sorry that write in Russian.
    There is a problem.
    Converts QdateTime (unix) in Hex QString
    Qt Code:
    1. QString time = QString("%1").arg(QDateTime::currentDateTime().toTime_t(),0,16).toUpper();
    To copy to clipboard, switch view to plain text mode 
    All OK.
    After trying to make
    Qt Code:
    1. QByteArray myHexArray = QByteArray::fromHex(time.toLatin1());
    To copy to clipboard, switch view to plain text mode 
    but leaves some crap.
    for example, I got HEX - 57640466
    If I manually insert it
    Qt Code:
    1. QByteArray myHexArray = QByteArray::fromHex("57640466");
    To copy to clipboard, switch view to plain text mode 
    That is the right thing happens at the output see
    Qt Code:
    1. 0x57 0x64 0x04 0x66
    To copy to clipboard, switch view to plain text mode 
    And if instead of the time value is inserted in the hex output is wrapped again in hex
    How so I do not understand.
    Even if everything is OK with the values, further reason
    if you take a separate index from 0 myHexArray not get 0x57, and
    [0] = 0x05, [1] = 0x07
    Help me please )
    Also from Google Translate:
    Please provide small, complete program that demonstrates the problem
    Просьба представить небольшую, полную программу, Ð´ÐµÐ¼Ð¾Ð½ÑÑ‚Ñ€Ð¸Ñ€ÑƒÑ Ñ‰ÑƒÑŽ проблему

  3. #3
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    Default Re: QDateTime to QString Hex to QByteArray - Problem (

    Quote Originally Posted by ChrisW67 View Post
    Courtesy of Google Translate

    Also from Google Translate:
    Please provide small, complete program that demonstrates the problem
    Просьба представить небольшую, полную программу, Ð´ÐµÐ¼Ð¾Ð½ÑÑ‚Ñ€Ð¸Ñ€ÑƒÑ Ñ‰ÑƒÑŽ проблему
    I see no reason to provide a demo version of the program.
    There's a protocol.
    In fact I described the problem seems to be normal, the problem is in the standard functions and it is not clear why instead of the array
    Qt Code:
    1. array[0] = 0xAB
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    output array
    2 key, rather than one
    Qt Code:
    1. array[0] = 0x0A
    2. array[1] = 0x0B
    To copy to clipboard, switch view to plain text mode 

  4. #4
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    Default Re: QDateTime to QString Hex to QByteArray - Problem (

    The reason I asked for a example that produces the problem is because you fail to describe the problem.
    Your first two pieces of code will give you a four byte QByteArray that you says "leaves some crap" (or something like it). You do not explain or show what that crap might be.
    The rest of your post manually builds an unrelated 4 byte QByteArray and demonstrates that the array contain four bytes.

    Here is the example:
    Qt Code:
    1. #include <QCoreApplication>
    2. #include <QDateTime>
    3. #include <QByteArray>
    4. #include <QString>
    5. #include <QDebug>
    6.  
    7. int main(int argc, char **argv)
    8. {
    9. QCoreApplication app(argc, argv);
    10.  
    11. uint timet = QDateTime::currentDateTime().toTime_t();
    12. qDebug() << "time_t value in hex: " << hex << timet;
    13.  
    14. QString time = QString("%1").arg(timet,0,16).toUpper();
    15. QByteArray myHexArray = QByteArray::fromHex(time.toLatin1());
    16. qDebug() << "time ==" << time;
    17. qDebug() << "myHexArray is" << myHexArray.size() << "bytes";
    18. qDebug() << "myHexArray == " << myHexArray.toHex();
    19. return 0;
    20. }
    To copy to clipboard, switch view to plain text mode 
    Output:
    Qt Code:
    1. time_t value in hex: 5767a69b
    2. time == "5767A69B"
    3. myHexArray is 4 bytes
    4. myHexArray == "5767a69b"
    To copy to clipboard, switch view to plain text mode 
    All looks good to me.
    Last edited by ChrisW67; 20th June 2016 at 09:44.

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