the qt app shows Chinese in messy code on windows when using UTF-8 encoding-format

[Princein]

Hi:
I developed a simple qt app on windows to test the qt Chinese UTF-8 encoding-format:

int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
   QTextCodec::setCodecForLocale(QTextCodec::codecForName("UTF-8"));
    QString strMessage = QString::fromLocal8Bit("我是UTF8编码的文件：");
    qDebug() << strMessage;
    return a.exec();
}

and my main.cpp file encoding format is UTF-8 without BOM, but when I run the app on windows, the app print string is "鎴戞槸UTF8缂栫爜鐨勬枃浠讹細" which I expect is "我是UTF8编码的文件：",it seems the string "我是UTF8编码的文件：" is converted to GB2312 encoding-format so shows the wrong string "鎴戞槸UTF8缂栫爜鐨勬枃浠讹細" in runtime,and the string "我是UTF8编码的文件：" shows right string "我是UTF8编码的文件：'' when the app runs on macos, I don't know why?
how to let the string "我是UTF8编码的文件：" show right on windows platform, thanks a lot!

[jsulm]

@Princein said in the qt app shows Chinese in messy code on windows when using UTF-8 encoding-format:

QString::fromLocal8Bit

this function expects 8bit ASCII encoded string (which can't represent Chinese) and not UTF8!
Use https://doc.qt.io/qt-5/qstring.html#fromUtf8 instead.

[Princein]

@jsulm
ok, now I change the main.cpp code and here is my main.cpp code

int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
   QTextCodec::setCodecForLocale(QTextCodec::codecForName("UTF-8"));
    QString strMessage = "我是UTF8编码的文件：";
    qDebug() << strMessage;
   std:: string str = "我是UTF8编码的文件：";
    cout << str <<endl;
    return a.exec();
}

the strMessage print "我是UTF8编码的文件：" on windows which just as I expected,but the str print "鎴戞槸UTF8缂栫爜鐨勬枃浠讹細" which is wrong, it seems the std::string not support utf-8 chinese,
how can I set to get the right utf-8 chinese "我是UTF8编码的文件：" when using the std::string? thanks a lot!

[jsulm]

@Princein You should read documentation: https://doc.qt.io/qt-5/qstring.html#toStdString
"The Unicode data is converted into 8-bit characters using the toUtf8()".

Try to use https://doc.qt.io/qt-5/qstring.html#toStdU16String

[Princein]

@jsulm

 std:: string str = "我是UTF8编码的文件：";
 cout << str <<endl;

I mean the std:: string is not related to QString, but print "鎴戞槸UTF8缂栫爜鐨勬枃浠讹細" which is wrong, if I want to print the str right that show "我是UTF8编码的文件：" when using std::string,
what should I do?

[jsulm]

@Princein Do you store your source code as UTF8? I mean, the string you want to print is in your source code, so the source code needs to be stored as UTF8 also. You can check in QtCreator settings.

[Christian Ehrlicher]

@jsulm said in the qt app shows Chinese in messy code on windows when using UTF-8 encoding-format:

Do you store your source code as UTF8?

Even today I would suggest to not store anything else than latin1 in the source code and use a proper translation for the rest - then one would never have such problems like here (which will maybe get even worse when using more than on os/compiler)

[jsulm]

@Christian-Ehrlicher You're probably right. I never use anything else than English strings in my/our sources, so never had such issues :-)