std::wstring_convert<Codecvt,Elem,Wide_alloc,Byte_alloc>::converted
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std::wstring_convert
Member functions
wstring_convert::converted
Defined in header
<locale>
std::size_t converted() const noexcept;
Returns the number of source characters that were successfully processed by the most recent from_bytes() or to_bytes() .
[edit] Return value
[edit] Example
Run this code
#include <codecvt> #include <iostream> #include <locale> #include <string> int main() { std::string utf8 = "z\u00df\u6c34\U0001d10b"; // or u8"zß水𝄋" // or "\x7a\xc3\x9f\xe6\xb0\xb4\xf0\x9d\x84\x8b"; std::cout << "original UTF-8 string size: " << utf8.size() << '\n'; // the UTF-8 - UTF-32 standard conversion facet std::wstring_convert <std::codecvt_utf8 <char32_t>, char32_t> cvt; // UTF-8 to UTF-32 std::u32string utf32 = cvt.from_bytes(utf8); std::cout << "UTF-32 string size: " << utf32.size() << '\n'; std::cout << "converted() == " << cvt.converted() << '\n'; // UTF-32 to UTF-8 utf8 = cvt.to_bytes(utf32); std::cout << "new UTF-8 string size: " << utf8.size() << '\n'; std::cout << "converted() == " << cvt.converted() << '\n'; }
Output:
original UTF-8 string size: 10 UTF-32 string size: 4 converted() == 10 new UTF-8 string size: 10 converted() == 4
[edit] Defect reports
The following behavior-changing defect reports were applied retroactively to previously published C++ standards.
| DR | Applied to | Behavior as published | Correct behavior |
|---|---|---|---|
| LWG 2174 | C++11 | wstring_convert::converted was not required to be noexcept
|
required |