Creating users for game(reading and parsing CSV file) - c++

Question

So I am working on a planets vs zombies type mock up game for class, and am using Qt Creator GUI with C++. One of the things that we are required to do is, on start-up, the game window will attempt to read two files: "pvz_levels.csv" and "pvz_players.csv" from a pre-specified home directory.
The levels file is of the form "level:sequence:rows:start:interval:decrement" and "sequence" itself is a comma separated list of the form (1,1,1,2,3,1,3,1,3,3) which is the sequence in which zombies appear. If this file does not exist in the directory, the program exits with an error.
The players file is of the form "timestamp:player:level"; the time of last play, name of player, and last attempted level, respectively. If this file does not exist, the program silently skips this operation and starts as a new player. If it does exist, the file must be read and parsed, and then used in the program for calculations and such.
So, I am having much trouble with reading and parsing these files. Furthermore, we are required to save the user data in these files, and on the next start-up the user should have the option to continue their game by selecting their respective user from a drop-down list. They should also be able to delete any users.
I am proficient enough with c++ basics but this is my first GUI experience and my prof did not go over it in much detail, so I require quite a bit of help with this project.
Thank you to anyone who is able to help!

Answer 1

Look up the code to an available "csv parser" which stands for "comma separated variable". You need is almost identical, except you use a semi-colon instead of a comma. It seems that by changing one character you parsing is done for you.
You may be able to find a csv parser that accepts the character to be used as the parsing character (I've seen them before).
If you wish I can find a suitable csv parser for your use, but now that you know what you're looking for "csv parser c++ code" it should be a quick Google away.
Also, most csv parsers expect strings to be enclosed to double quotes (") but that is easily modifable.

Answer 2

Some hints:
Just open the File using QFile. Set up a QTextStream and use QTextStream::readLine() to read all Lines into QStringList. Now use QString::split() on the QString saved in the list to get the single values stored in this line. From there you can easily use QString::to* functions to cast the values into your desired type.
For saving just reverse the procedure.
Set up a line using: QString("%1,%2,%3").arg(timestamp).arg(player).arg(level) and put it into your QTextStream. If the stream is connected to a file, this will be written into the file.

Answer 3

I've implemented successfully the CSV reading like this:
std::unique_ptr<QFile> csv_worker(new QFile(resource_path));
QTextStream input_csv(csv_worker.get());
QList<QStringList> data
while(!input_csv.atEnd())
{
//removes the carriage return symbol and splits the elements
QStringList line = input_csv.readLine().remove(QRegExp("\r")).split(","); //replace here with :
data << line;
}
csv_worker->close();
It reads the complete file, each line generates a QStringList.
For the second element in the QStringList, let's say (1,1,1,2,3,1,3,1,3,3}, you have to additionally split that in a sub-QStringList, removing then brackets with something like this:
QStringList sequence = data[i][1].remove(QRegExp("{")).remove(QRegExp("}")).split(",");