How to read line from file

[jacek]

countnr++; so is correct?

if line request is 10 break it...

Yes, but you read only the first line from the file.

[patrik08]

now run

qDebug() << "### line 4 " << file_get_line("1.html",4); 
 
QString HTML_Edit::file_get_line(QString fullFileName,int linenr)
{
    QFile file(fullFileName);
    QString inside = "";  
    if (file.exists()) {
                if (file.open(QFile::ReadOnly | QFile::Text)) {
                  inside =file.readAll();
                  file.close();
                }
    }
    QStringList list = inside.split("\n"); 
return QString(list.at(linenr));   /* line zero is  1 Advanced Search */
}

qDebug() << "### line 4 " << file_get_line("1.html",4); 

QString HTML_Edit::file_get_line(QString fullFileName,int linenr)
{
    QFile file(fullFileName);
    QString inside = "";  
    if (file.exists()) {
                if (file.open(QFile::ReadOnly | QFile::Text)) {
                  inside =file.readAll();
                  file.close();
                }
    }
    QStringList list = inside.split("\n"); 
return QString(list.at(linenr));   /* line zero is  1 Advanced Search */
}

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1.html

1 Advanced Search
2 Rate This Thread
3 ExcellentExcellent
4 GoodGood
5 AverageAverage
6 BadBad
7 TerribleTerrible
8 Posting Rules

1 Advanced Search
2 Rate This Thread
3 ExcellentExcellent
4 GoodGood
5 AverageAverage
6 BadBad
7 TerribleTerrible
8 Posting Rules

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[jacek]

now run

Yes, but IMO your first attempt was better (except for the bug).

I would implement it like this (not tested):

QString HTML_Edit::file_get_line( const QString& fullFileName, int lineNr )
{
    QString result;  
    QFile file( fullFileName );
    if( file.open( QIODevice::ReadOnly | QIODevice::Text ) ) {
       QTextStream in( &file );
       int currentLineNr = 0; // or 1
       while( ! in.atEnd() ) {
          QString line( in.readLine() );
          if( currentLineNr == lineNr ) {
             result = line;
             break;
          }
          currentLineNr += 1;
       }
    }
    return result;
}

QString HTML_Edit::file_get_line( const QString& fullFileName, int lineNr )
{
    QString result;  
    QFile file( fullFileName );
    if( file.open( QIODevice::ReadOnly | QIODevice::Text ) ) {
       QTextStream in( &file );
       int currentLineNr = 0; // or 1
       while( ! in.atEnd() ) {
          QString line( in.readLine() );
          if( currentLineNr == lineNr ) {
             result = line;
             break;
          }
          currentLineNr += 1;
       }
    }
    return result;
}

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[patrik08]

tested ... work .... ... is also utils to QTextStream /&/ QTcpSocket

QString HTML_Edit::file_get_line(QString fullFileName,int linenr)
{
    QString result;  
    QFile file( fullFileName );
    if( file.open( QIODevice::ReadOnly | QIODevice::Text ) ) {
       QTextStream in( &file );
       int currentLineNr = 0; // or 1
       while( ! in.atEnd() ) {
          QString line( in.readLine() );
          if( currentLineNr == linenr ) {   /* only rewrite here .. lineNr */
             result = line;
             break;
          }
          currentLineNr += 1;
          /*qDebug() << "### linerr  " << currentLineNr; */
       }
    }
    return result;
}

QString HTML_Edit::file_get_line(QString fullFileName,int linenr)
{
    QString result;  
    QFile file( fullFileName );
    if( file.open( QIODevice::ReadOnly | QIODevice::Text ) ) {
       QTextStream in( &file );
       int currentLineNr = 0; // or 1
       while( ! in.atEnd() ) {
          QString line( in.readLine() );
          if( currentLineNr == linenr ) {   /* only rewrite here .. lineNr */
             result = line;
             break;
          }
          currentLineNr += 1;
          /*qDebug() << "### linerr  " << currentLineNr; */
       }
    }
    return result;
}

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