Simple example of QCommandLineParser

[nagardd]

Hi All,

I would like to write (for self learning) very simple command application with options using QCommandLineParser and QCommandLineOption.

Example:
app.exe -a1 -a2

Options will do some operations like number operations and print to console.
Let's say c=a+b and then print c.

I am beginner of QT and won't able to understand how using QCommandLineParser tell application to run code for a1 and/or a2 options.
Could you please tell me how to do this?

Btw. I've read good article:
http://www.ics.com/blog/whats-new-qt-52-qcommandlineparser#.VMlcjk10zBR

But I am not sure if there is explained how to run some code/functionality for specified option.

Thanks,

[SGaist]

Hi,

Yes it does explain that however did you took a look a the example provided "here":http://doc.qt.io/qt-5/qcommandlineparser.html#details ?

[nagardd]

Thank you SGaist!

After reading the blog and your link I have managed to create console application with arguments.

Depends on the argument, I can run for example calculation functionality.
I am posting my code and maybe it might be useful for somebody:

@#include <QCoreApplication>
#include <QCommandLineOption>
#include <QCommandLineParser>
#include <QTextStream>
#include <QDebug>
#include <QString>
#include <QStringList>

int main(int argc, char *argv[])
{
QCoreApplication a(argc, argv);
QCoreApplication::setApplicationName("Application Name");
QCoreApplication::setApplicationVersion("Version: 1");

QCommandLineParser parser;
parser.setApplicationDescription("Description: This is example of console application");
parser.addHelpOption();
parser.addVersionOption();

QCommandLineOption showCalculation(QStringList() << "o" << "opt", QCoreApplication::translate("main", "Option is: fr") \
                                   ,QCoreApplication::translate("main", "opt"), "1");
parser.addOption(showCalculation);

parser.process(a);

const QStringList args = parser.optionNames();
if (args.size() < 1) {
    fprintf(stderr, "%s\n", qPrintable(QCoreApplication::translate("main", "Error: Must specify an argument.")));
    parser.showHelp(1);
}

QString opt1 = parser.value(showCalculation);

if (opt1 != "fr") {
    fprintf(stderr, "%s\n", qPrintable(QCoreApplication::translate("main", "Error: Invalid format argument. Must be fr")));
    parser.showHelp(1);
}

if (opt1 == "fr")
{
    int a =4, b = 5, c=0;
    c=a+b;
    qDebug() << "Sum: " << c;
}

//return a.exec&#40;&#41;;
return 0;

}
@

Example from command line:

c:\untitled2.exe
Error: Must specify an argument.
Usage: untitled2.exe [options]
This is example of console application

Options:
-?, -h, --help Displays this help.
-v, --version Displays version information.
-o, --opt <opt> Option is: fr

c:\untitled2.exe -o abc
Error: Invalid format argument. Must be fr
Usage: untitled2.exe [options]
This is example of console application

Options:
-?, -h, --help Displays this help.
-v, --version Displays version information.
-o, --opt <opt> Option is: fr

c:\untitled2.exe -o fr
Sum: 9

[SGaist]

Why don't you use the "isSet":http://doc.qt.io/qt-5/qcommandlineparser.html#isSet-2 function ?

Also why two ifs ? Using else would make more sense