Try parse QString to int

column

Hello,

Looking for function that parses QString to int. In case it can't parse , for example, string contains some non numeric's it should return error.

Something like tryparse() in other languages.

J.Hilk

@column
lucky, you're using Qt:
http://doc.qt.io/qt-5/qstring.html#toInt

Gojir4

Hello,

You can use QString::toInt() method. Which take an optional boolean pointer as argument, giving the result of the conversion.

Just a small example with output

#include <QCoreApplication>
#include <QDebug>

void test1();
int main(int argc, char *argv[])
{
    QCoreApplication a(argc, argv);

    test1();
    return 0;
}


void test1_toInt(const QString &s){
    bool ok;
    int i = s.toInt(&ok, 10);
    qInfo() <<  s << " toInt(dec) -> " << i << (ok ? "OK" : "FAILED");
    i = s.toInt(&ok, 16);
    qInfo() <<  s << " toInt(hex) -> " << i << (ok ? "OK" : "FAILED");
}


void test1(){

    test1_toInt("123");
    test1_toInt("12H");
    test1_toInt("H12");
    test1_toInt("FF");
    test1_toInt("GHI");
}

Output:

"123"  toInt(dec) ->  123 OK
"123"  toInt(hex) ->  291 OK
"12H"  toInt(dec) ->  0 FAILED
"12H"  toInt(hex) ->  0 FAILED
"H12"  toInt(dec) ->  0 FAILED
"H12"  toInt(hex) ->  0 FAILED
"FF"  toInt(dec) ->  0 FAILED
"FF"  toInt(hex) ->  255 OK
"GHI"  toInt(dec) ->  0 FAILED
"GHI"  toInt(hex) ->  0 FAILED