std::wstring_convert<Codecvt,Elem,Wide_alloc,Byte_alloc>::wstring_convert (3) - Linux Manuals

std::wstring_convert<Codecvt,Elem,Wide_alloc,Byte_alloc>::wstring_convert: std::wstring_convert<Codecvt,Elem,Wide_alloc,Byte_alloc>::wstring_convert

NAME

std::wstring_convert<Codecvt,Elem,Wide_alloc,Byte_alloc>::wstring_convert - std::wstring_convert<Codecvt,Elem,Wide_alloc,Byte_alloc>::wstring_convert

Synopsis

wstring_convert() : wstring_convert( new Codecvt ) { } (1)
explicit wstring_convert( Codecvt* pcvt ); (2)
wstring_convert( Codecvt* pcvt, state_type state); (3)
explicit wstring_convert( const byte_string& byte_err, (4)
const wide_string& wide_err = wide_string() );
wstring_convert(const std::wstring_convert&) = delete; (5) (since C++14)

1) Default constructor.
2) Constructs the wstring_convert object with a specified conversion facet, using default-constructed values for the shift state and the error strings
3) Constructs the wstring_convert object with a specified conversion facet and specified shift state, using default-constructed values for the error strings
4) Constructs the wstring_convert object with specified error strings, using new Codecvt as the conversion facet and the default-constructed state_type as shift state.
5) The copy constructor is deleted, wstring_convert is not CopyConstructible

Parameters

pcvt - pointer to the conversion facet of type Codecvt (behavior is undefined if this pointer is null)
state - initial value of the conversion shift state
byte_err - narrow string to display on errors
wide_err - wide string to display on errors

Defect reports

The following behavior-changing defect reports were applied retroactively to previously published C++ standards.

DR Applied to Behavior as published Correct behavior
P0935R0 C++11 default constructor was explicit made implicit

Example

// Run this code

  #include <locale>
  #include <utility>
  #include <codecvt>

  // utility wrapper to adapt locale-bound facets for wstring/wbuffer convert
  template<class Facet>
  struct deletable_facet : Facet
  {
      using Facet::Facet; // inherit constructors
      ~deletable_facet() {}
  };

  int main()
  {
      // UTF-16le / UCS4 conversion
      std::wstring_convert<
           std::codecvt_utf16<char32_t, 0x10ffff, std::little_endian>
      > u16to32;

      // UTF-8 / wide string conversion with custom messages
      std::wstring_convert<std::codecvt_utf8<wchar_t>> u8towide("Error!", L"Error!");

      // GB18030 / wide string conversion facet
      typedef deletable_facet<std::codecvt_byname<wchar_t, char, std::mbstate_t>> F;
      std::wstring_convert<F> gbtowide(new F("zh_CN.gb18030"));
  }