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Thread: Update txt file after clearing line in Qt

  1. #1
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    Default Update txt file after clearing line in Qt

    I am trying to update the text file after I cleared a line in the file. When I print after the clear the line is actually cleared but when I reopen the txt file the line is still there.
    Here is the Code.

    Qt Code:
    1. void myAccounts::on_removeB_clicked()
    2. {
    3. myFile = new QFile("accountsDB.txt");
    4. if(!myFile->open(QIODevice::Text | QIODevice::ReadWrite))
    5. qDebug()<<"1!!"<<endl;
    6. else
    7. qDebug()<<"3!!"<<endl;
    8. stream= new QTextStream(myFile);
    9.  
    10. while(!stream->atEnd())
    11. {
    12. line=stream->readLine();
    13. list = line.split(",");
    14. qDebug()<<ui->tableWidget->currentItem()->text()<<endl;
    15. qDebug()<<list[0]<<endl;
    16. qDebug()<<line<<endl;
    17.  
    18. if(ui->tableWidget->currentItem()->text() == list[0] || ui->tableWidget->currentItem()->text() == list[1])
    19. {
    20. line.clear();
    21. qDebug()<<line<<endl;
    22. myFile->close();
    23. }
    24. }
    25. ui->tableWidget->removeRow(ui->tableWidget->currentRow());
    26. }
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    Last edited by Lykurg; 20th December 2010 at 13:13.

  2. #2
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    Default Re: Update txt file after clearing line in Qt

    I see no instruction to save the new content to the file.

  3. #3
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    Default Re: Update txt file after clearing line in Qt

    You will have to read the whole file and hold that data in a temp variable, clear the file content, remove the line from the content, and write back the content with the line cleared.
    ==========================signature=============== ==================
    S.O.L.I.D principles (use them!):
    https://en.wikipedia.org/wiki/SOLID_...iented_design)

    Do you write clean code? - if you are TDD'ing then maybe, if not, your not writing clean code.

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