Progress of reading the file

[ModeZt]

I read the input text file line by line.

dataFile = new QFile(fileName);
dataFile->open(QIODevice::ReadOnly | QIODevice::Text);
dataStream = new QTextStream(dataFile);
while( !dataStream->atEnd() ) {
    line = dataStream->readLine();
    ...
}

dataFile = new QFile(fileName);
dataFile->open(QIODevice::ReadOnly | QIODevice::Text);
dataStream = new QTextStream(dataFile);
while( !dataStream->atEnd() ) {
    line = dataStream->readLine();
    ...
}

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The file is > 200Mb.
I need to update a progress bar while i analize the lines.
I was going to use

100 * currentLine / numberOfLines

100 * currentLine / numberOfLines

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but how do i get the number of lines in the file?..

Thx!

[wysota]

You can't. You'd have to read the file first and count newline characters What you can do is to calculate an average line length based on the file size. A simple approximation is to calculate not lines but bytes in the file assuming that each line has more or less similar number of characters.