QString Split() issue.

Uberlinc

Here is the file that I'm reading in from at its entirety:

20210101,23,27,44,1,41,18
20210107,20,44,20,31,13,34
20210114,23,24,36,28,5,8
20210121,23,33,44,8,38,22
20210128,18,6,16,30,17,34
20210204,29,8,20,3,4,12
20210211,11,28,37,38,5,9
20210218,34,4,32,25,40,3
20210225,26,34,25,31,38,5
20210304,31,3,41,28,12,2
20210311,37,39,41,28,26,19
20210318,2,11,38,43,38,23
20210325,45,7,8,37,14,12

Uberlinc

@JonB said in QString Split() issue.:

@Uberlinc

tmp = line.split(",");
qDebug() << line << tmp.length()  << tmp;

22:05:08: Starting /home/linc/Documents/Workspace/Qt/build-SimpleFile-Desktop-Debug/SimpleFile...
"20210107,20,44,20,31,13,34" 7 ("20210107", "20", "44", "20", "31", "13", "34")
"20210114,23,24,36,28,5,8" 7 ("20210114", "23", "24", "36", "28", "5", "8")
"20210121,23,33,44,8,38,22" 7 ("20210121", "23", "33", "44", "8", "38", "22")
"20210128,18,6,16,30,17,34" 7 ("20210128", "18", "6", "16", "30", "17", "34")
"20210204,29,8,20,3,4,12" 7 ("20210204", "29", "8", "20", "3", "4", "12")
"20210211,11,28,37,38,5,9" 7 ("20210211", "11", "28", "37", "38", "5", "9")
"20210218,34,4,32,25,40,3" 7 ("20210218", "34", "4", "32", "25", "40", "3")
"20210225,26,34,25,31,38,5" 7 ("20210225", "26", "34", "25", "31", "38", "5")
"20210304,31,3,41,28,12,2" 7 ("20210304", "31", "3", "41", "28", "12", "2")
"20210311,37,39,41,28,26,19" 7 ("20210311", "37", "39", "41", "28", "26", "19")
"20210318,2,11,38,43,38,23" 7 ("20210318", "2", "11", "38", "43", "38", "23")
"20210325,45,7,8,37,14,12" 7 ("20210325", "45", "7", "8", "37", "14", "12")
"" 1 ("")
ASSERT failure in QList<T>::operator[]: "index out of range", file /usr/include/x86_64-linux-gnu/qt5/QtCore/qlist.h, line 552

JonB

@Uberlinc So? How many elements in the list does the output show when it ASSERTS?

J.Hilk

@Uberlinc said in QString Split() issue.:

"" 1 ("")

looks like you have an empty line in your file.
I would suggest simply skipping, if your don't get the required amount of entries after the split

strTmp = linest.split(",");

if(strTmp.size() < 7){
    qDebug() << "Invalid linest:" << linest;
    return;
}

Uberlinc

@J-Hilk said in QString Split() issue.:

looks like you have an empty line in your file.
I would suggest simply skipping, if your don't get the required amount of entries after the split

I did see that, and so I checked the file.
Yes, there was a blank line at the end of the file.
So, I removed it.
Definitely not there now.

The same error occurred.

Weird?

Here is the code to read the file.
Could the error be here instead?

void MainWindow::readInfile(QString filename)
{
    QFile file(filename);
    if(!file.open(QFile::ReadOnly |
                  QFile::Text))
    {
        QMessageBox::about(this, "Error", "Could not open file for reading");
        return;
    }

    QTextStream stream(&file);
    QString line = stream.readLine();
    while (!line.isNull())
    {
        // process information
        line = stream.readLine();
        loadVec(line);
    }


    QMessageBox::about(this, "Done", "File contents read in!");
    file.close();
}

jsulm

@Uberlinc said in QString Split() issue.:

Could the error be here instead?

Please first check the string you're splitting!
This is first thing to do in such a situation...
You also should ALWAYS check the indexes when handling data! Not just think it will be exactly what you expect.

goloviznin.k

Hey, maybe this will help you somehow:

tmp = line.split(",", QString::SkipEmptyParts);
		for (int i = 0; i < tmp.count(); ++i) 
		{
			arrstuff[i] = tmp[i].toInt();
			std::cout << arrstuff[i] << " ";
		}

Uberlinc

@jsulm said in QString Split() issue.:

Please first check the string you're splitting!
This is first thing to do in such a situation...

I did.
Please see the qDebug output above.
It definitely contains commas.
I have removed any and all spaces/carriage returns at the end of the file.
From what I can see, the lines are indeed being read in as per QDebug output above.

Thanks.

J.Hilk

@Uberlinc line.isNull() != line.isEmpty()

also you're reading the line twice and not checking against empty with the 2nd read...

QTextStream stream(&file);
    while (!stream.atEnd())
    {
        // process information
        QString line = stream.readLine();
        if(!line.isEmpty())
           loadVec(line);
    }

jsulm

@Uberlinc said in QString Split() issue.:

Please see the qDebug output above

Where?
You posted new code but no new debug output as far as I can see.
Please post the string you're trying to split. You expect it to have at least 5 commas, right?
Does the string in question contain 5 commas?

Uberlinc

I think I've sorted it now.
It was an error in the file read loop.

Thank you for your assistance.