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Read a file txt

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  • L LatitudeFr

    @J-Hilk thank you for your reply
    the result :
    a05a7025-381d-4b2b-b155-222b7a1c82b8-image.png
    can i send you the code by e-mail ?

    J.HilkJ Offline
    J.HilkJ Offline
    J.Hilk
    Moderators
    wrote on last edited by
    #13

    @LatitudeFr no need, you need to accumulate your data.

    like @mrjj said, your serial port(?) doesn't notify you when all data arrived, it does when any data arrived.

    and you have to store that and decide when and how all data arrived.

    from what you showed, I would say your message ends with a 0x2320aka # and space.

    QByteArray accumulatedData; 
    QByteArray expectedEnd=  QByteArray::fromHex("2320");
    void MainWindow::updateGUI_sonde(QByteArray data_sonde) {
        qDebug() << Q_FUNC_INFO << data_sonde.toHex(' '); // <------ this one
        accumulatedData.append(data_sonde);
     
        if(!accumulatedData.endsWith(expectedEnd))
           return;
        //ecrire les données***********************
        QFile file("data_sonde.txt");
        QStringList line_data ;
    
        if( file.open(QIODevice::Append)) {
           QTextStream data(&file);
           data<<accumulatedData;
    
           file.close();
           accumulatedData.clear();
    
    //lire les données*************************
           QStringList line ;
           if (!file.open(QFile::ReadOnly | QFile::Text)) {
                  qDebug()<<"File not exists";
           } else {
                QTextStream lire_data(&file);
                while (!lire_data.atEnd()) {
                        qDebug() << lire_data.readLine();
                }
                file.close();
          }
       }
    }
    

    Be aware of the Qt Code of Conduct, when posting : https://forum.qt.io/topic/113070/qt-code-of-conduct


    Q: What's that?
    A: It's blue light.
    Q: What does it do?
    A: It turns blue.

    L 1 Reply Last reply
    2
    • J.HilkJ J.Hilk

      @LatitudeFr no need, you need to accumulate your data.

      like @mrjj said, your serial port(?) doesn't notify you when all data arrived, it does when any data arrived.

      and you have to store that and decide when and how all data arrived.

      from what you showed, I would say your message ends with a 0x2320aka # and space.

      QByteArray accumulatedData; 
      QByteArray expectedEnd=  QByteArray::fromHex("2320");
      void MainWindow::updateGUI_sonde(QByteArray data_sonde) {
          qDebug() << Q_FUNC_INFO << data_sonde.toHex(' '); // <------ this one
          accumulatedData.append(data_sonde);
       
          if(!accumulatedData.endsWith(expectedEnd))
             return;
          //ecrire les données***********************
          QFile file("data_sonde.txt");
          QStringList line_data ;
      
          if( file.open(QIODevice::Append)) {
             QTextStream data(&file);
             data<<accumulatedData;
      
             file.close();
             accumulatedData.clear();
      
      //lire les données*************************
             QStringList line ;
             if (!file.open(QFile::ReadOnly | QFile::Text)) {
                    qDebug()<<"File not exists";
             } else {
                  QTextStream lire_data(&file);
                  while (!lire_data.atEnd()) {
                          qDebug() << lire_data.readLine();
                  }
                  file.close();
            }
         }
      }
      
      L Offline
      L Offline
      LatitudeFr
      wrote on last edited by
      #14

      @J-Hilk it works very well thank you very much but please how I can read just the last line

      mrjjM 1 Reply Last reply
      0
      • L LatitudeFr

        @J-Hilk it works very well thank you very much but please how I can read just the last line

        mrjjM Offline
        mrjjM Offline
        mrjj
        Lifetime Qt Champion
        wrote on last edited by mrjj
        #15

        @LatitudeFr

        Hi
        it doesn't work like that :)

        Say you send "This is my line" from the board.

        then you get more than one read signal and data comes like

        Thi
        is m
        y li
        ne

        so you need to add them together to make a line of it.
        In this case we know we got all data when we see #

        there is no last line. it comes in bytes and we make a line from that.

        L 1 Reply Last reply
        2
        • mrjjM mrjj

          @LatitudeFr

          Hi
          it doesn't work like that :)

          Say you send "This is my line" from the board.

          then you get more than one read signal and data comes like

          Thi
          is m
          y li
          ne

          so you need to add them together to make a line of it.
          In this case we know we got all data when we see #

          there is no last line. it comes in bytes and we make a line from that.

          L Offline
          L Offline
          LatitudeFr
          wrote on last edited by
          #16

          @mrjj with this code the problem is solved but I would need to read every time I press the button just the last line and not all the lines
          the code :
          QByteArray accumulatedData;
          QByteArray expectedEnd= QByteArray::fromHex("2320");
          void MainWindow::updateGUI_sonde(QByteArray data_sonde) {
          // qDebug() << Q_FUNC_INFO << data_sonde.toHex(' '); // <------ this one
          accumulatedData.append(data_sonde);

          if(!accumulatedData.endsWith(expectedEnd))
             return;
          
          //ecrire les données***********************
          QFile file("data_sonde.txt");
          QStringList line_data ;
          
          if( file.open(QIODevice::Append)) {
             QTextStream data(&file);
             data<<accumulatedData;
          
             file.close();
             accumulatedData.clear();
          

          //lire les données*************************
          QStringList line ;
          if (!file.open(QFile::ReadOnly | QFile::Text)) {
          qDebug()<<"File not exists";
          } else {
          QTextStream lire_data(&file);
          while (!lire_data.atEnd()) {
          line =lire_data.readLine().split(' ');
          if(!line.contains(("para")))
          {
          if(!line.contains(("data")))
          {
          if(!line.contains(("#")))
          {

                                     bool ok;
                                     float ph =line.at(0).toDouble(&ok);
                                     if(!ok)
                                     continue;
                                     qDebug()<<ph;
                                     ui->sonde_label->setNum(ph);
          
                           qDebug() << line;
                                 }
                          }
                      }
                  }
                  file.close();
            }
          

          }
          }

          the file.txt
          875033b3-1f5a-47f4-af8a-1028e228595a-image.png

          the result
          6394b266-46f8-4a2a-a90d-520e91c30737-image.png

          1 Reply Last reply
          0
          • mrjjM Offline
            mrjjM Offline
            mrjj
            Lifetime Qt Champion
            wrote on last edited by
            #17

            Hi
            Since you now wait until you see #

            if(!accumulatedData.endsWith(expectedEnd))
               return;
            

            then you might want to use

            file.open(QIODevice::Read | QIODevice::Truncate | QIODevice::Text);
            and not
            file.open(QIODevice::Append)

            so you only save the complete line once. Else if you test more than once and don't delete the file between,
            it will have more than 1 data line /set. Like you show in the notepad image.

            L 1 Reply Last reply
            0
            • mrjjM mrjj

              Hi
              Since you now wait until you see #

              if(!accumulatedData.endsWith(expectedEnd))
                 return;
              

              then you might want to use

              file.open(QIODevice::Read | QIODevice::Truncate | QIODevice::Text);
              and not
              file.open(QIODevice::Append)

              so you only save the complete line once. Else if you test more than once and don't delete the file between,
              it will have more than 1 data line /set. Like you show in the notepad image.

              L Offline
              L Offline
              LatitudeFr
              wrote on last edited by LatitudeFr
              #18

              @mrjj thank your for your reply but i need file.open(QIODevice::Append) to write on the file
              for the first time it reads only one data since in our file there is only one data but when I press the button for the second time it reads 2 data since we have 2 data in the file but I would need to read just the last data

              for the first time
              1.PNG
              2.PNG

              for the second time
              3.PNG
              4.PNG

              mrjjM 1 Reply Last reply
              0
              • L LatitudeFr

                @mrjj thank your for your reply but i need file.open(QIODevice::Append) to write on the file
                for the first time it reads only one data since in our file there is only one data but when I press the button for the second time it reads 2 data since we have 2 data in the file but I would need to read just the last data

                for the first time
                1.PNG
                2.PNG

                for the second time
                3.PNG
                4.PNG

                mrjjM Offline
                mrjjM Offline
                mrjj
                Lifetime Qt Champion
                wrote on last edited by mrjj
                #19

                @LatitudeFr

                Why ?

                it will only write a full line since we wait until we see #

                so when your load part runs, then it can load the full line.

                Using append when opening the files allows appending more to it next time.
                but unless board sent many different data lines and you only want the last one, I'm not sure why
                you need append ?

                (update) Ahh. you do want to send more than one data line and store all in a file but then later
                only use the last data ?

                1 Reply Last reply
                0
                • J.HilkJ Offline
                  J.HilkJ Offline
                  J.Hilk
                  Moderators
                  wrote on last edited by
                  #20
                  QByteArray accumulatedData; 
                  QByteArray expectedEnd=  QByteArray::fromHex("2320");
                  void MainWindow::updateGUI_sonde(QByteArray data_sonde) {
                      qDebug() << Q_FUNC_INFO << data_sonde.toHex(' '); // <------ this one
                      accumulatedData.append(data_sonde);
                   
                      if(!accumulatedData.endsWith(expectedEnd))
                         return;
                      //ecrire les données***********************
                      QFile file("data_sonde.txt");
                      QStringList line_data ;
                  
                      if( file.open(QIODevice::Append)) {
                         QTextStream data(&file);
                         data<<accumulatedData;
                  
                         file.close();
                         
                  //lire les données*************************
                         QStringList line ;
                         if (!file.open(QFile::ReadOnly | QFile::Text)) {
                                qDebug()<<"File not exists";
                         } else {
                              QTextStream lire_data(&file);
                              lire_data.seek(file.size() - accumulatedData.size());
                              while (!lire_data.atEnd()) {
                                      qDebug() << lire_data.readLine();
                              }
                              file.close();
                        }
                     }
                     accumulatedData.clear(); //We now clear at the very end
                  }
                  

                  Be aware of the Qt Code of Conduct, when posting : https://forum.qt.io/topic/113070/qt-code-of-conduct


                  Q: What's that?
                  A: It's blue light.
                  Q: What does it do?
                  A: It turns blue.

                  mrjjM 1 Reply Last reply
                  2
                  • J.HilkJ J.Hilk
                    QByteArray accumulatedData; 
                    QByteArray expectedEnd=  QByteArray::fromHex("2320");
                    void MainWindow::updateGUI_sonde(QByteArray data_sonde) {
                        qDebug() << Q_FUNC_INFO << data_sonde.toHex(' '); // <------ this one
                        accumulatedData.append(data_sonde);
                     
                        if(!accumulatedData.endsWith(expectedEnd))
                           return;
                        //ecrire les données***********************
                        QFile file("data_sonde.txt");
                        QStringList line_data ;
                    
                        if( file.open(QIODevice::Append)) {
                           QTextStream data(&file);
                           data<<accumulatedData;
                    
                           file.close();
                           
                    //lire les données*************************
                           QStringList line ;
                           if (!file.open(QFile::ReadOnly | QFile::Text)) {
                                  qDebug()<<"File not exists";
                           } else {
                                QTextStream lire_data(&file);
                                lire_data.seek(file.size() - accumulatedData.size());
                                while (!lire_data.atEnd()) {
                                        qDebug() << lire_data.readLine();
                                }
                                file.close();
                          }
                       }
                       accumulatedData.clear(); //We now clear at the very end
                    }
                    
                    mrjjM Offline
                    mrjjM Offline
                    mrjj
                    Lifetime Qt Champion
                    wrote on last edited by
                    #21

                    @J-Hilk
                    Cool but wont he just get the last # and not the data line ?

                    J.HilkJ 1 Reply Last reply
                    0
                    • mrjjM mrjj

                      @J-Hilk
                      Cool but wont he just get the last # and not the data line ?

                      J.HilkJ Offline
                      J.HilkJ Offline
                      J.Hilk
                      Moderators
                      wrote on last edited by
                      #22

                      @mrjj he shouldn't, wee accumulate the whole message, before we actually write:

                      void MainWindow::updateGUI_sonde(QByteArray data_sonde) {
                          qDebug() << Q_FUNC_INFO << data_sonde.toHex(' '); // <------ this one
                          accumulatedData.append(data_sonde);
                       
                          if(!accumulatedData.endsWith(expectedEnd))
                             return;
                      

                      Be aware of the Qt Code of Conduct, when posting : https://forum.qt.io/topic/113070/qt-code-of-conduct


                      Q: What's that?
                      A: It's blue light.
                      Q: What does it do?
                      A: It turns blue.

                      L 1 Reply Last reply
                      2
                      • J.HilkJ J.Hilk

                        @mrjj he shouldn't, wee accumulate the whole message, before we actually write:

                        void MainWindow::updateGUI_sonde(QByteArray data_sonde) {
                            qDebug() << Q_FUNC_INFO << data_sonde.toHex(' '); // <------ this one
                            accumulatedData.append(data_sonde);
                         
                            if(!accumulatedData.endsWith(expectedEnd))
                               return;
                        
                        L Offline
                        L Offline
                        LatitudeFr
                        wrote on last edited by
                        #23

                        @J-Hilk @mrjj thank you it works very well

                        1 Reply Last reply
                        0

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