How to change string into QString?

c++, qstring, qt, string

Solution

If by string you mean `std::string` you can do it with this method:

QString QString::fromStdString(const std::string & str)

std::string str = "Hello world";
QString qstr = QString::fromStdString(str);

If by string you mean Ascii encoded `const char *` then you can use this method:

QString QString::fromAscii(const char * str, int size = -1)

const char* str = "Hello world";
QString qstr = QString::fromAscii(str);

If you have `const char *` encoded with system encoding that can be read with QTextCodec::codecForLocale() then you should use this method:

QString QString::fromLocal8Bit(const char * str, int size = -1)

const char* str = "zażółć gęślą jaźń";      // latin2 source file and system encoding
QString qstr = QString::fromLocal8Bit(str);

If you have `const char *` that's UTF8 encoded then you'll need to use this method:

QString QString::fromUtf8(const char * str, int size = -1)

const char* str = read_raw("hello.txt"); // assuming hello.txt is UTF8 encoded, and read_raw() reads bytes from file into memory and returns pointer to the first byte as const char*
QString qstr = QString::fromUtf8(str);

There's also method for `const ushort *` containing UTF16 encoded string:

QString QString::fromUtf16(const ushort * unicode, int size = -1)

const ushort* str = read_raw("hello.txt"); // assuming hello.txt is UTF16 encoded, and read_raw() reads bytes from file into memory and returns pointer to the first byte as const ushort*
QString qstr = QString::fromUtf16(str);

Problem

Original source