Convert a QString to an uint8_t

[Pantoufle]

Hello,

here is my problem :

I have a Qstring that contains "1.2" for example, what i want to do, is having two uint8_t , one with the number 1 inside and the other one with the number 2 inside. (Note that i would want the number, not the Ascii carac).

How i do :

    QPair<uint8_t, uint8_t> _Version = 1.2;
    QStringList versionsNumbers = _Version.split(".");
    _Version.first = static_cast<uint8_t>(versionsNumbers.at(0).toInt());
    _Version.second = static_cast<uint8_t>(versionsNumbers.at(1).toInt());

From what i saw, i cant just make a ".toInt()" without a cast or i would get a warning. And there is no function "toUin8_t", i just find .toUShort.

Is this the right solution?

[jsulm]

@Pantoufle said in Convert a QString to an uint8_t:

QPair<uint8_t, uint8_t> _Version = 1.2;

I don't get it: you are talking about QString, but here you use a QPair?
What you can do is simply split the string at '.':

QStringList parts = str.split('.');
uint8_t = static_cast<uint8_t>(parts[0].toInt());
// same for the second number

And yes you have to cast.

[Pantoufle]

Oh sorry i miss copy my code :p

Here the real one :

    QString VersionString = "1.2";
    QPair<uint8_t, uint8_t> _Version;
    QStringList versionsNumbers = VersionString.split(".");
    _Version.first = static_cast<uint8_t>(versionsNumbers.at(0).toInt());
    _Version.second = static_cast<uint8_t>(versionsNumbers.at(1).toInt());

[VRonin]

Probably not worth it but given it's uint8_t you can use:

const QString _Version = "1.2";
const auto versionsNumbers = _Version.splitRef(".");
std::pair<uint8_t, uint8_t> verNums = std::make_pair<uint8_t, uint8_t>(versionsNumbers.at(0).at(0).unicode()-'0',versionsNumbers.at(1).at(0).unicode()-'0');

[Pantoufle]

That seems more complicated than my solution to be honest :p

[VRonin]

@Pantoufle said in Convert a QString to an uint8_t:

That seems more complicated than my solution to be honest :p

Indeed, hence my "Probably not worth it". It's more efficient though

[J.Hilk]

@Pantoufle said in Convert a QString to an uint8_t:

versionsNumbers

if you're not using versionsNumbers elsewhere in your current scope, I would use splitRef

also list/array size checking before accessing 0 and 1 would be good to have as well.

[Pantoufle]

@VRonin

Ok good to know.

@J-Hilk

I don't use it elsewhere.
For array size check, i always though that when you use .at(i) instead of [i], there is an automatic check to avoid reading overflow.
Maybe I'm wrong.

[VRonin]

@Pantoufle said in Convert a QString to an uint8_t:

when you use .at(i) instead of [i], there is an automatic check to avoid reading overflow.

No, value(i) does, at(i) lets it up to you to check

[Pantoufle]

Ok really good things to know thanks for your help guys