How to convert a unicode string to its unicode escapes?

Question

Say I have a text "Բարև Hello Здравствуй". (I save this code in QString, but if you know other way to store this text in c++ code, you'r welcome.) How can I convert this text to Unicode escapes like this "\u1330\u1377\u1408\u1415 Hello \u1047\u1076\u1088\u1072\u1074\u1089\u1090\u1074\u1091\u1081" (see here)?

Answer 1

#include <cstdio>

#include <QtCore/QString>
#include <QtCore/QTextStream>

int main() {
  QString str = QString::fromWCharArray(L"Բարև Hello Здравствуй");
  QString escaped;
  escaped.reserve(6 * str.size());
  for (QString::const_iterator it = str.begin(); it != str.end(); ++it) {
    QChar ch = *it;
    ushort code = ch.unicode();
    if (code < 0x80) {
      escaped += ch;
    } else {
      escaped += "\\u";
      escaped += QString::number(code, 16).rightJustified(4, '0');
    }
  }
  QTextStream stream(stdout);
  stream << escaped << '\n';
}

Note this loops over UTF-16 code units, not actual code points.

Answer 2

I assume you're doing code-generation (of JavaScript, maybe?)

QString is like a collection of QChar. Loop through the contents, and on each QChar call the unicode method to get the ushort (16-bit integer) value.

Then format each character like "\\u%04X", i.e. \u followed by the 4-digit hex value.

NB. You may need to swap the two bytes (the two hex characters) to get the right result depending on the platform you're running on.