Qt convert unicode entities

7
votes

In QT 5.4 and C++ I try to decode a string that has unicode entities.

I have this QString:

QString string = "file\u00d6\u00c7\u015e\u0130\u011e\u00dc\u0130\u00e7\u00f6\u015fi\u011f\u00fc\u0131.txt";

I want to convert this string to this: fileÖÇŞİĞÜİçöşiğüı.txt

I tried QString's toUtf8 and fromUtf8 methods. Also tried to decode it character by character.

Is there a way to convert it by using Qt?

3
c++windowsqtvisual-studio-2012unicode
Probably your console is not configured to print Unicode. If you are executing on Windows Prompt, try this stackoverflow.com/questions/2492077/… – gibertoni
Thank you. Yes windows console also has unicode problems, but I need to decode it in my cpp codes. – trante
Your string literal contains Unicode escapes, characters which probably won't fit in 8 bits. And on al Qt platforms, char is 8 bits. You'll probably need a wide literal: L"file\u00d6\u00c7\u015e\u0130..." – MSalters
offtopic: for me this string looks like something what should be a application configuration setting and not hard-coded. – Marek R

3 Answers

7
votes

Qt provides a macro called QStringLiteral for handling string literals correctly.

Here's a full working example:

#include <QString>
#include <QDebug>

int main(void) {
   QString string = QStringLiteral("file\u00d6\u00c7\u015e\u0130\u011e\u00dc\u0130\u00e7\u00f6\u015fi\u011f\u00fc\u0131.txt");
   qDebug() << string;

   return 0;
}

As mentioned in the above comments, you do need to print to a console that supports these characters for this to work.

2
votes

I have just tested this code: 

int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
    QString s = "file\u00d6\u00c7\u015e\u0130\u011e\u00dc\u0130\u00e7\u00f6\u015fi\u011f\u00fc\u0131.txt";
    qDebug() << s.length();  //Outputs: 22
    qDebug() << s;           //Outputs: fileÖÇŞİĞÜİçöşiğüı.txt
    return a.exec();
}

This is with Qt 5.4 on ubuntu, so it looks like your problem is with some OS only.

0
votes
#include <QTextDocument>

QTextDocument doc;

QString string = "file\u00d6\u00c7\u015e\u0130\u011e\u00dc\u0130\u00e7\u00f6\u015fi\u011f\u00fc\u0131.txt";
doc.setHtml(string);                   // to convert entities to text
QString result = doc.toPlainText();    // result = "fileÖÇŞİĞÜİçöşiğüı.txt"

NOT USEFUL if you have a CONSOLE app QTextDocument needs the GUI module.