[Interest] Working with QDateTime's timezone information

[Jan Kundrát]

Hi Thiago,

On 06/12/12 17:31, Thiago Macieira wrote:
> There isn't a way. The QTimezone feature has been pending for years.

Right, it seems that the utcOffset won't survive a serialization to
QDataStream (using Qt 4.8.1):

    QDateTime blah = QDateTime::fromString("1997-07-16T19:20:30+09:45",
Qt::ISODate);
    qDebug() << blah << blah.toLocalTime() << blah.toUTC();
    QByteArray buf;
    QDataStream writing(&buf, QIODevice::ReadWrite);
    writing << blah;

    QDataStream reading(&buf, QIODevice::ReadOnly);
    QDateTime anotherDate;
    reading >> anotherDate;
    qDebug() << anotherDate << anotherDate.toLocalTime() <<
anotherDate.toUTC();

$ TZ=Europe/Prague ./myapp
QDateTime("Wed Jul 16 19:20:30 1997") QDateTime("Wed Jul 16 19:20:30
1997") QDateTime("Wed Jul 16 09:35:30 1997")
QDateTime("Wed Jul 16 19:20:30 1997") QDateTime("Wed Jul 16 19:20:30
1997") QDateTime("Wed Jul 16 19:20:30 1997")

Weird thing is that the output doesn't change regardless if I set TZ to
America/Chicago, Europe/Prague or Asia/Tehran. Weird, and a bug, I guess.

Looks like I'm really out of luck here.

> You're entirely on your own if you touch the internals. Behaviour might change 
> in any release.

Fair enough. The better question is then "any chances of making these
two functions public in a 4.x release"?

With kind regards,
Jan

-- 
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