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Selecting multiple files for reading

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  • JonBJ JonB

    @suslucoder
    You receive a list of filenames. You have to go through one-by-one (that's called "iterating" or "iteration"), one file a time, doing whatever you want to do to each one with QFile. I don't honestly see what else you would expect?!

    ? Offline
    ? Offline
    A Former User
    wrote on last edited by
    #7

    @JonB If I could think and do all of this at once, I wouldn't ask for help. You don't have to be this hard every time. I'm probably younger than you, and I'm making an effort to learn. It shouldn't be that hard to understand

    Christian EhrlicherC jsulmJ JonBJ 3 Replies Last reply
    0
    • ? A Former User

      @JonB If I could think and do all of this at once, I wouldn't ask for help. You don't have to be this hard every time. I'm probably younger than you, and I'm making an effort to learn. It shouldn't be that hard to understand

      Christian EhrlicherC Offline
      Christian EhrlicherC Offline
      Christian Ehrlicher
      Lifetime Qt Champion
      wrote on last edited by Christian Ehrlicher
      #8

      @suslucoder But even then you should know how to iterate over a container, sorry.

      https://stackoverflow.com/questions/498455/best-way-to-iterate-through-a-container

      Qt Online Installer direct download: https://download.qt.io/official_releases/online_installers/
      Visit the Qt Academy at https://academy.qt.io/catalog

      ? 1 Reply Last reply
      4
      • ? A Former User

        @JonB If I could think and do all of this at once, I wouldn't ask for help. You don't have to be this hard every time. I'm probably younger than you, and I'm making an effort to learn. It shouldn't be that hard to understand

        jsulmJ Offline
        jsulmJ Offline
        jsulm
        Lifetime Qt Champion
        wrote on last edited by jsulm
        #9

        @suslucoder Well this is Qt forum, not basic programming one. That's why people can give somewhat harsh replies if you ask about basic programming stuff not related to Qt. This is something you should understand.
        Iterating trough a list is one of the basic programming concepts. You should do some research for such basic stuff at your own before asking here. For example using Google you can find: https://stackoverflow.com/questions/16825376/qt-foreach-loop-ordering-vs-for-loop-for-qlist

        https://forum.qt.io/topic/113070/qt-code-of-conduct

        ? 1 Reply Last reply
        3
        • ? A Former User

          @JonB If I could think and do all of this at once, I wouldn't ask for help. You don't have to be this hard every time. I'm probably younger than you, and I'm making an effort to learn. It shouldn't be that hard to understand

          JonBJ Offline
          JonBJ Offline
          JonB
          wrote on last edited by JonB
          #10

          @suslucoder said in Selecting multiple files for reading:

          @JonB If I could think and do all of this at once, I wouldn't ask for help. You don't have to be this hard every time. I'm probably younger than you, and I'm making an effort to learn. It shouldn't be that hard to understand

          I think I explained it very gently & clearly! And told you what you need to do, and explained what the term "iteration" is. So I'm sorry you feel like that, I believe I am one of the people here who is prepared to explain things the most! :) Maybe, if you can, don't take my words as harsh, because they are not intended like that! I'm a pussy cat really :-;

          ? 2 Replies Last reply
          0
          • JonBJ JonB

            @suslucoder said in Selecting multiple files for reading:

            @JonB If I could think and do all of this at once, I wouldn't ask for help. You don't have to be this hard every time. I'm probably younger than you, and I'm making an effort to learn. It shouldn't be that hard to understand

            I think I explained it very gently & clearly! And told you what you need to do, and explained what the term "iteration" is. So I'm sorry you feel like that, I believe I am one of the people here who is prepared to explain things the most! :) Maybe, if you can, don't take my words as harsh, because they are not intended like that! I'm a pussy cat really :-;

            ? Offline
            ? Offline
            A Former User
            wrote on last edited by
            #11

            @JonB Yes, after seeing the other answers, I understood that you answered my question very kindly. Thank you for your help

            1 Reply Last reply
            1
            • Christian EhrlicherC Christian Ehrlicher

              @suslucoder But even then you should know how to iterate over a container, sorry.

              https://stackoverflow.com/questions/498455/best-way-to-iterate-through-a-container

              ? Offline
              ? Offline
              A Former User
              wrote on last edited by
              #12

              @Christian-Ehrlicher yes I don't know, is it a shame that I don't know?

              Christian EhrlicherC 1 Reply Last reply
              0
              • jsulmJ jsulm

                @suslucoder Well this is Qt forum, not basic programming one. That's why people can give somewhat harsh replies if you ask about basic programming stuff not related to Qt. This is something you should understand.
                Iterating trough a list is one of the basic programming concepts. You should do some research for such basic stuff at your own before asking here. For example using Google you can find: https://stackoverflow.com/questions/16825376/qt-foreach-loop-ordering-vs-for-loop-for-qlist

                ? Offline
                ? Offline
                A Former User
                wrote on last edited by
                #13

                @jsulm Okey.

                1 Reply Last reply
                0
                • ? A Former User

                  @Christian-Ehrlicher yes I don't know, is it a shame that I don't know?

                  Christian EhrlicherC Offline
                  Christian EhrlicherC Offline
                  Christian Ehrlicher
                  Lifetime Qt Champion
                  wrote on last edited by
                  #14

                  @suslucoder Please start with basic c and c++ - everything else will not work out properly. And I'm pretty sure so will tell you the same.

                  Qt Online Installer direct download: https://download.qt.io/official_releases/online_installers/
                  Visit the Qt Academy at https://academy.qt.io/catalog

                  1 Reply Last reply
                  1
                  • JonBJ JonB

                    @suslucoder said in Selecting multiple files for reading:

                    @JonB If I could think and do all of this at once, I wouldn't ask for help. You don't have to be this hard every time. I'm probably younger than you, and I'm making an effort to learn. It shouldn't be that hard to understand

                    I think I explained it very gently & clearly! And told you what you need to do, and explained what the term "iteration" is. So I'm sorry you feel like that, I believe I am one of the people here who is prepared to explain things the most! :) Maybe, if you can, don't take my words as harsh, because they are not intended like that! I'm a pussy cat really :-;

                    ? Offline
                    ? Offline
                    A Former User
                    wrote on last edited by
                    #15

                    @JonB I want to ask you something.

                    I did it in the way you said. Now i can select multiple files.
                    After selecting, i want to do some operations. But my code do it just for one file. The other files are not functional.

                    Is there any way to do it like, do these for every different files.
                    I will share you my iteration, i hope it is correct:

                    Q_UNUSED(b);
                    
                       QStringList fileNames;
                    
                       fileNames = QFileDialog::getOpenFileNames(nullptr,
                                                                 ("choose"), "up.sakla", ("choosen(*.up)"));
                    
                      for (auto xfile : fileNames)
                      {
                    
                       QFile file (xfile);
                       file.open(QIODevice::ReadOnly);
                       QDataStream in(&file);    // read the data serialized from the file
                       QString str;
                       qint32 a;
                         qDebug() << str << a;
                       in >> str >> a;
                    
                    jsulmJ 1 Reply Last reply
                    0
                    • ? A Former User

                      @JonB I want to ask you something.

                      I did it in the way you said. Now i can select multiple files.
                      After selecting, i want to do some operations. But my code do it just for one file. The other files are not functional.

                      Is there any way to do it like, do these for every different files.
                      I will share you my iteration, i hope it is correct:

                      Q_UNUSED(b);
                      
                         QStringList fileNames;
                      
                         fileNames = QFileDialog::getOpenFileNames(nullptr,
                                                                   ("choose"), "up.sakla", ("choosen(*.up)"));
                      
                        for (auto xfile : fileNames)
                        {
                      
                         QFile file (xfile);
                         file.open(QIODevice::ReadOnly);
                         QDataStream in(&file);    // read the data serialized from the file
                         QString str;
                         qint32 a;
                           qDebug() << str << a;
                         in >> str >> a;
                      
                      jsulmJ Offline
                      jsulmJ Offline
                      jsulm
                      Lifetime Qt Champion
                      wrote on last edited by jsulm
                      #16

                      @suslucoder So, did you select more than one file? How many entries do you have in fileNames? Did you use debugger to see what happens?
                      Add

                      for (auto xfile : fileNames)
                      {
                          qDebug() << xfile;
                      

                      to see what happens. There are so many things you can do to find out what happens...

                      https://forum.qt.io/topic/113070/qt-code-of-conduct

                      ? 1 Reply Last reply
                      0
                      • jsulmJ jsulm

                        @suslucoder So, did you select more than one file? How many entries do you have in fileNames? Did you use debugger to see what happens?
                        Add

                        for (auto xfile : fileNames)
                        {
                            qDebug() << xfile;
                        

                        to see what happens. There are so many things you can do to find out what happens...

                        ? Offline
                        ? Offline
                        A Former User
                        wrote on last edited by A Former User
                        #17

                        @jsulm said in Selecting multiple files for reading:

                        qDebug() << xfile;

                        Yes i select and i can see them. I want to do such a thing:

                        do some operation
                        for every file that i select

                        jsulmJ J.HilkJ 2 Replies Last reply
                        0
                        • ? A Former User

                          @jsulm said in Selecting multiple files for reading:

                          qDebug() << xfile;

                          Yes i select and i can see them. I want to do such a thing:

                          do some operation
                          for every file that i select

                          jsulmJ Offline
                          jsulmJ Offline
                          jsulm
                          Lifetime Qt Champion
                          wrote on last edited by
                          #18

                          @suslucoder What do you think you print out to qDebug here:

                          QString str;
                          qint32 a;
                          qDebug() << str << a;
                          in >> str >> a;
                          

                          https://forum.qt.io/topic/113070/qt-code-of-conduct

                          ? 1 Reply Last reply
                          0
                          • jsulmJ jsulm

                            @suslucoder What do you think you print out to qDebug here:

                            QString str;
                            qint32 a;
                            qDebug() << str << a;
                            in >> str >> a;
                            
                            ? Offline
                            ? Offline
                            A Former User
                            wrote on last edited by
                            #19

                            @jsulm I wrote it for see the content of my file. Im asking another thing..

                            jsulmJ 1 Reply Last reply
                            0
                            • ? A Former User

                              @jsulm I wrote it for see the content of my file. Im asking another thing..

                              jsulmJ Offline
                              jsulmJ Offline
                              jsulm
                              Lifetime Qt Champion
                              wrote on last edited by
                              #20

                              @suslucoder Do you really think the order of the two last lines is correct?

                              https://forum.qt.io/topic/113070/qt-code-of-conduct

                              ? 1 Reply Last reply
                              1
                              • ? A Former User

                                @jsulm said in Selecting multiple files for reading:

                                qDebug() << xfile;

                                Yes i select and i can see them. I want to do such a thing:

                                do some operation
                                for every file that i select

                                J.HilkJ Offline
                                J.HilkJ Offline
                                J.Hilk
                                Moderators
                                wrote on last edited by
                                #21

                                @suslucoder said in Selecting multiple files for reading:

                                I want to do such a thing:
                                do some operation
                                for every file that i select

                                so, what's stoping you ?


                                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.

                                ? 1 Reply Last reply
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                                • J.HilkJ J.Hilk

                                  @suslucoder said in Selecting multiple files for reading:

                                  I want to do such a thing:
                                  do some operation
                                  for every file that i select

                                  so, what's stoping you ?

                                  ? Offline
                                  ? Offline
                                  A Former User
                                  wrote on last edited by
                                  #22

                                  @J-Hilk I dont know how to do it. Im asking for any idea

                                  1 Reply Last reply
                                  0
                                  • jsulmJ jsulm

                                    @suslucoder Do you really think the order of the two last lines is correct?

                                    ? Offline
                                    ? Offline
                                    A Former User
                                    wrote on last edited by
                                    #23

                                    @jsulm No you are right

                                    1 Reply Last reply
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