c++ - How do you use unicode in Qt? -

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• retrieve unicode code points > u+ffff qchar 3 answers

i use magnifying glass (u+1f50e) unicode symbol in qlineedit field. figured out how use 16-bit unicode symbols using qchar have no idea how use unicode symbol represented 5 hex digits.

qlineedit edit = new qlineedit(); edit.setfont(qfont("segoe ui symbol")); edit.settext(????); 

so far have tried:

edit.settext(qstring::fromutf8("\u0001f50e")); 

which gave compiler warning:

warning c4566: character represented universal-character-name '\ud83ddd0e' cannot represented in current code page 

and showed as: ??

i tried:

edit.settext(qstring("\u0001f50e")); 

which gave compiler warning:

warning c4566: character represented universal-character-name '\ud83ddd0e' cannot represented in current code page (1252) 

and gave: ??

i tried try qchar. tried switching encoding of cpp file , copying , pasting symbol in, didn't work.

you know answer - specify proper utf-16 string.

unicode codepoints above u+ffff represented in utf-16 using surrogate pair, 2 16bit codeunits acting represent full unicode codepoint value. u+1f50e, surrogate pair u+d83d u+dd0e.

in qt, utf-16 codeunit represented qchar, need 2 qchar values, eg:

edit.settext(qstring::fromwchararray(l"\xd83d\xdd0e")); 

or:

edit.settext(qstring::fromstdwstring(l"\xd83d\xdd0e")); 

assuming platform sizeof(wchar_t) 2 , not 4.

in example, tried using qstring::fromutf8(), gave invalid utf-8 string. u+1f50e, should have looked instead:

edit.settext(qstring::fromutf8("\xf0\x9f\x94\x8e")); 

you can use qstring::fromucs4() instead:

uint cp = 0x1f50e; edit.settext(qstring::fromucs4(&cp, 1));