how to read hex value data from text file and store into array?



  • I have a file with hex values saved as hex.txt which has

    0x09,0xFF,0xD5,0x3C,0x06,0x7C,0x0A...total is 498 bytes

    Now I need to copy this 498 bytes values to below array at a particular position starting from [4] to [498]..value is listed in text file as comma separated field. Also "0x" prefix is there

    given array is unsigned char hex[508] = {0};

    How I do it in qt?any help


  • Lifetime Qt Champion

    Hi,

    Taking your sample values, do you mean you only want to keep 3C067C0A... ?



  • thanks for reply...no i want to keep same 0x3C,0x06...etc..



  • Well, it's not directly linked to Qt. Here is what I suggest.

    Using QRegExp or QRegularExpression depending on your Qt version you can split the different values, which you can then convert from QString to quint8.


  • Lifetime Qt Champion

    So you basically want to just remove the first 15bytes of the line ?



  • no i want to just copy this 498 bytes data into an array...


  • Lifetime Qt Champion

    So basically:

    QByteArray, fileContent = myFile.readAll();
    memcpy(&hex[4], fileContent.data(), fileContent.size());
    

    ?



  • @SGaist said:

    So basically:

    QByteArray, fileContent = myFile.readAll();
    memcpy(&hex[4], fileContent.data(), fileContent.size());
    

    ?

    I don't think so, he apparently has the binary values he's interesting in ASCII format in the file.



  • i have open and read this file properly in c but for storing this data in array not get it any idea...

    #include <stdio.h>
    #include <stdlib.h>
    int main()
    {
    FILE *f;
    char c;
    f=fopen("1.txt","r");
    while((c=fgetc(f))!=EOF)
    {
    printf("%c",c);
    }
    fclose(f);
    return 0;
    }


  • Moderators

    Read the file content in a QByteArray using QFile::readAll().
    Then call split(',') on that byte array.
    You will get a list of QByteArray like:

    ["0x09","0xFF","0xD5","0x3C","0x06","0x7C","0x0A"...]
    

    Now you can loop over all the elements of the list and call QByteArray::fromHex(...).toInt() to convert from hex to integer.



  • @jsulm said:

    Read the file content in a QByteArray using QFile::readAll().
    Then call split(',') on that byte array.

    Nice idea, no need for regular expressions indeed!



  • ok for now i done till this.
    my file is 1.txt, which contains simply this "1A,2C,0A"

    unsigned char temp[3]={0}
    QByteArray bb("0x");
    QByteArray aa;

    QString line;
    QFile file1(filename);
    if(file1.open(QIODevice::ReadOnly | QIODevice::Text)){
    line=file1.readAll();
    QStringList strings2 = line.split(QRegExp("\W+"), QString::SkipEmptyParts);
    int n = strings2.size();

        for(x=0;x<n;x++){
               qDebug() << strings2.at(x) << "  ";
               aa = strings2.at(x).toLocal8Bit();      // at this aa =1A first loop, and so on.
               bb=bb.append(aa);    // bb= 0x1A for first loop , and so on
               bb ="0x";                     // initialise 'bb'
               /*
                *
                * in this portion is there any way  i can save value of 'bb' to my unsigned    char  temp[ ]?
                *so that i can do something like temp[x]=bb ?? 
                */
    
               if(x==n) break;
              }               
         }

  • Moderators

    It is not really clear what you want: do you want to store a character represented by the hex value or the integer value?
    So, how should temp look after you store bb there?
    What is this supposed to do?

    bb=bb.append(aa);    // bb= 0x1A for first loop , and so on
    bb ="0x";
    

    you first assign a value and then overwrite it with "0x".
    Why do you need 0x?

    In my previous post I already suggested how to convert hex string to integer.


  • Lifetime Qt Champion

    From your latest text sample, what about:

    QByteArray dataFromFile = file.readAll();
    QByteArray aa = "0x" +  dataFromFile.replace(",", "");
    

    But as @jsulm asked, what is your final goal with these data ?



    1. I have a file with hex values saved as hex.txt which has
      0x04,0x2C,0x64,0x00,0xB6,0x03,0xFA,0x84,0x87,0x6A,0x74,0x18,0x01,0x64,0x79,0x13,0x09,0x6A,0xCB,0xED,0x3D,0x9C,0x79,0x88,0x49,0x4A,0x2E,0xE8,0x89,0x24,0xF7,0xDD,0x04,0xA9,0x09,0xE7,0xE5,0x14,0xF7,0x5B,0xC5,0x49,0x38,0x10,0xFA,0x5C,0xFA,0x99,0xC4,0x0D,0x74,0xE0,0x3A,0x45,0xE8,0x64,0xCC,0xBB,0x72,0x57,0x31,0x63,0xF9,0x7F,0x46,0x48,0xF4,0xE8,0x91,0x5B,0xF8,0xED,0x07,0x9B,0x09,0x07,0x0D,0x64,0xF7,0x64,0xC7,0x5A,0xB8,0x17,0xCD,0xBC,0x6A,0xA9,0xC3,0x9D,0xEF,0x96,0x9D,0x62,0xF5,0xDD,0x83,0xD9,0x45,0x0F,0x99,0x4B,0xF6,0x63,0x41,0x29,0x38,0xE0,0x4A,0xCD,0xF9,0x94,0xC3,0x1D,0xAE,0xB8,0x96,0x3D,0x69,0x82,0x8C,0xFF,0x29,0xF9,0x2A,0xF6,0x85,0x50,0x45,0x1A,0x7E,0xF8,0x26,0x66,0x86,0x43,0x48,0x4B,0x3E,0xF9,0x96,0xD4,0x6A,0x33,0xC3,0x6B,0x75,0xFD,0x29,0x95,0xAA,0x27,0xC4,0xBD,0xF7,0x0F,0x99,0x1D,0xEB,0x9C,0x84,0xFB,0x7B,0xF8,0x4D,0x3A,0xFA,0x12,0x43,0xC9,0x43,0x0F,0x66,0x52,0xF7,0x6F,0x87,0x4A,0x36,0xE9,0xD5,0x84,0x8B,0x9A,0x8B,0xFF,0xC1,0x0F,0x2D,0x25,0x8B,0x99,0xCE,0xFE,0xC3,0xFF,0x0E,0xC9,0xF8,0x88,0x83,0xD9,0x83,0xD8,0x5D,0x91,0xF5,0x76,0xC7,0x3A,0xF8,0xE0,0x86,0x71,0xF7,0x7C,0x04,0x3A,0xFA,0xD8,0x95,0x69,0x4B,0x8F,0xC5,0xFA,0xFB,0xEF,0xBD,0x19,0xF6,0x05,0xC6,0xB8,0x7B,0x16,0xD5,0x71,0xF6,0x7D,0x46,0xD7,0xB7,0xC0,0xE5,0x11,0xF7,0x75,0x04,0x4A,0x3A,0xE1,0x72,0xD9,0x4B,0x96,0x89,0xFF,0xFF,0xDF,0x82,0xF2,0xF4,0x65,0x44,0x3B,0xB8,0xF0,0xF9,0xF9,0x43,0x50,0xC4,0x9D,0xFE,0x37,0x62,0xB8,0xA7,0x88,0x43,0xE9,0xC1,0xEF,0xB5,0x50,0xF7,0x87,0x85,0x17,0x40,0xE8,0x01,0x98,0x4A,0x86,0xC7,0xF7,0xFF,0x0F,0x31,0x38,0x4A,0x0B,0x44,0x38,0x7E,0xF8,0x59,0xE8,0x49,0x8B,0xC3,0xD9,0xFF,0xEF,0x72,0xE0,0x4A,0x0C,0xC7,0x29,0x3E,0xF8,0x45,0x33,0x7C,0x1B,0x02,0xDA,0x3F,0xF8,0xB1,0xF8,0x45,0x80,0x44,0x19,0xBE,0xE0,0xD6,0xC8,0x45,0x04,0xC3,0xF9,0x05,0x1F,0xA1,0x6B,0x7C,0x94,0xC3,0xF7,0xFB,0x0F,0xA3,0x2F,0x3F,0x11,0x27,0x42,0xF7,0x44,0x1F,0x65,0x62,0x52,0x42,0x4A,0x34,0x22,0x13,0x21,0x54,0x18,0x22,0x85,0xFF,0x43,0x32,0xB8,0xA5,0xF7,0xFF,0x12,0xF2,0x1F,0xC1,0x68,0x48,0x86,0x2F,0x22,0xF8,0x26,0x23,0xFF,0x0F,0xF6,0xFF,0x3F,0x77,0x45,0x1F,0x1F,0x17,0xF4,0x74,0x34,0x36,0x73,0x3F,0x26,0xF2,0x1F,0x6F,0x92,0x41,0xF7,0xFF,0x77,0xA6,0xF4,0x8F,0x4F,0xF4,0xF9,0x33,0x75,0x32,0xF4,0xF1,0xF8,0xF1,0x1F,0x8F,0x46,0x36,0x06,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0xA2,0xE4
      total is 498 bytes

    2)Now I need to copy this 498 bytes values (same to same) to below array at a particular position starting from [8] to [498]

    given the array in that array i want to store above text file data.....
    unsigned char hex[508]={
    0x5A,0xA5,0x0B,0x01,0xF4,0x01,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
    0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00};


  • Moderators

    temp[x]=static_cast<unsigned char>(QByteArray::fromHex(bb).toInt());
    

  • Qt Champions 2016

    @sachin786
    Judging from your C code you don't have a text file at all but rather a binary file where the characters are saved. Assuming this is the case you read the data into a byte array (as already suggested) and just copy the relevant parts into a new byte array.

    QFile inputFile("myFileName.txt", QFile::ReadOnly);
    if (!inputFile.open())
        ; //< Handle open errors here
    
    QByteArray binary = inputFile.readAll();   //< binary contains the file now
    
    unsigned char hex[508]; //< This is your array
    
    qint32 start = 4, size = 498;
    ::memcpy(hex + start, binary.constData(), size); //< Copy the binary data
    

    If, on the other hand, you indeed have a text file as shown in the above post, then you read the text into a string (as already suggested yet again) and split by the comma separator. You then convert the resulting strings into one byte integers and copy them over to the new byte array.

    QFile inputFile("myFileName.txt", QFile::ReadOnly | QFile::Text);
    if (!inputFile.open())
        ; //< Handle open errors here
    
    QTextStream in(&inputFile);
    QString text = in.readAll();   //< text contains the file now
    
    QStringList bytes = text.split(',');  //< Split the text into bytes
    
    QByteArray binary; //< Prepare the byte array
    binary.reserve(bytes.size());
    
    bool ok = true;
    foreach (QString byte, bytes)  {
        unsigned char hexChar = byte.toInt(&ok, 0); //< Convert string to integer according to C-style rules
        if (!ok)
            ; //< Error while converting, handle accordingly
    
        binary.append(hexChar); //< Append the char to the byte array
    }
    
    // And finally, copy the data:
    
    unsigned char hex[508]; //< This is your array
    
    qint32 start = 4, size = 498;
    ::memcpy(hex + start, binary.constData(), size); //< Copy the binary data
    

    EDIT: Alternatively the last snippet could be modified so you can save the data directly while converting:

    QFile inputFile("myFileName.txt", QFile::ReadOnly | QFile::Text);
    if (!inputFile.open())
        ; //< Handle open errors here
    
    QTextStream in(&inputFile);
    QString text = in.readAll();   //< text contains the file now
    
    QStringList bytes = text.split(',');  //< Split the text into bytes
    
    bool ok = true;
    
    qint32 start = 4, size = 498;
    for (qint32 i = 0, bytesNumber = bytes.size(), offset = start; i < bytesNumber && i < size; i++, offset++)  {
        unsigned char hexChar = byte.toInt(&ok, 0); //< Convert string to integer according to C-style rules
        if (!ok)
            ; //< Error while converting, handle accordingly
    
        hex[offset] = hexChar;
    }
    


  • @kshegunov thanks for reply...
    #include "qtquick1applicationviewer.h"
    #include <QApplication>
    #include <QtCore>
    #include <QDebug>
    int main(int argc, char *argv[])
    {
    QApplication app(argc, argv);

    QtQuick1ApplicationViewer viewer;
    viewer.addImportPath(QLatin1String("modules"));
    viewer.setOrientation(QtQuick1ApplicationViewer::ScreenOrientationAuto);
    viewer.setMainQmlFile(QLatin1String("qrc:/main.qml"));
    viewer.showExpanded();
    
    
    bool ok = true;
    QString filename="/home/anas/myQtApp/sachin2hex/hex.txt";
    QFile inputFile(filename);
    QByteArray binary; //< Prepare the byte array
    QStringList bytes;
    int i=0;
    
    unsigned char hex[508]={0x5A,0xA5,0x0B,0x01,0xF4,0x01,0x00,0x00,....position from[4] to [498] bytes data ///  << same as mention above
    
    if(inputFile.open(QIODevice::ReadOnly | QIODevice::Text)){
        QTextStream in(&inputFile);
        QString text = in.readAll();   //< text contains the file now
    
        bytes = text.split(',');
        qDebug() << "bytes :: " << bytes;
    
        binary.reserve(bytes.size());
    
        foreach (QString byte, bytes)  {
            unsigned char hexChar = byte.toInt(&ok, 0); //< Convert string to integer according to C-style rules
            if (!ok)
                ; //< Error while converting, handle accordingly
    
            binary.append(hexChar); //< Append the char to the byte array
        }
    
        qint32 start = 4, size = 498;
        ::memcpy(hex + start, binary.constData(), size); //< Copy the binary data
    
    
    }
    
    for(i=0;i<508;i++) printf("%c", hex[i]);
    
    return app.exec();
    

    }

    it print garbage for hex[ ]......


  • Qt Champions 2016

    @sachin786

    it print garbage for hex[ ]......

    What do you expect to be printed exactly? The data is binary so any of the elements that can't be displayed will be printed as gibberish ... 0x01, 0x00 are non-printable characters, so you'd see (depending on the platform) squares or other strange symbols, this doesn't necessarily mean the data is corrupted, only that it's interpreted in a erroneous way.


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