无法让“wcout”在多个代码页中打印unicode字符串，同时让“cout”继续工作
请帮助我让这 3 行代码一起工作。
std::wcout<<"abc "<<L'\u240d'<<" defg "<<L'א'<<" hijk"<<std::endl;
std::cout<<"hello world from cout! \n";
std::wcout<<"hello world from wcout! \n";
输出：
abc hello world from cout!
我试过：
#include <io.h>
#include <fcntl.h>
_setmode(_fileno(stdout), _O_U8TEXT);
问题： “wcout”失败
尝试过：
std::locale mylocale("");
std::wcout.imbue(mylocale);
和：
SetConsoleOutputCP(1251);
和
setlocale(LC_ALL, "");
和
SetConsoleCP(CP_UTF8)
没有任何效果
Microsoft 需要对
_setmode()wcoutwcin#include <iostream>
#include <locale>
#include <locale.h>
#include <stdlib.h>
#ifndef MS_STDLIB_BUGS // Allow overriding the autodetection.
/* The Microsoft C and C++ runtime libraries that ship with Visual Studio, as
* of 2017, have a bug that neither stdio, iostreams or wide iostreams can
* handle Unicode input or output. Windows needs some non-standard magic to
* work around that. This includes programs compiled with MinGW and Clang
* for the win32 and win64 targets.
*/
# if ( _MSC_VER || __MINGW32__ || __MSVCRT__ )
/* This code is being compiled either on MS Visual C++, or MinGW, or
* clang++ in compatibility mode for either, or is being linked to the
* msvcrt.dll runtime.
*/
# define MS_STDLIB_BUGS 1
# else
# define MS_STDLIB_BUGS 0
# endif
#endif
#if MS_STDLIB_BUGS
# include <io.h>
# include <fcntl.h>
#endif
#if !HAS_APP17_FILESYSTEM && !HAS_TS_FILESYSTEM && __has_include(<filesystem>)
# include <filesystem> /* MSVC has this header, but not the standard API. */
# if __cpp_lib_filesystem >= 201703
# define HAS_CPP17_FILESYSTEM 1
# endif
#endif
#if !HAS_CPP17_FILESYSTEM && __has_include(<experimental/filesystem>)
# include <experimental/filesystem>
/* Microsoft screws this one up, too, by not defining the feature-test
* macro specified by the standard.
*/
# if __cpp_lib_experimental_filesystem >= 201406 || MS_STDLIB_BUGS
# define HAS_TS_FILESYSTEM 1
/* With g++6, this requires -lstdc++fs, AFTER this source file on the
* command line.
*/
# endif
#endif
#if HAS_CPP17_FILESYSTEM
using std::filesystem::absolute;
using std::filesystem::current_path;
using std::filesystem::directory_entry;
using std::filesystem::directory_iterator;
using std::filesystem::is_directory;
using std::filesystem::exists;
using std::filesystem::path;
#elif HAS_TS_FILESYSTEM
using std::experimental::filesystem::absolute;
using std::experimental::filesystem::current_path;
using std::experimental::filesystem::directory_entry;
using std::experimental::filesystem::directory_iterator;
using std::experimental::filesystem::is_directory;
using std::experimental::filesystem::exists;
using std::experimental::filesystem::path;
#else
# error "This library has neither <filesystem> nor <experimental/filesystem>."
#endif
void init_locale(void)
// Does magic so that wcout can work.
{
#if MS_STDLIB_BUGS
// Windows needs a little non-standard magic.
constexpr char cp_utf16le[] = ".1200"; // UTF-16 little-endian locale.
setlocale( LC_ALL, cp_utf16le );
_setmode( _fileno(stdout), _O_WTEXT );
/* Repeat for _fileno(stdin), if needed. */
#else
// The correct locale name may vary by OS, e.g., "en_US.utf8".
constexpr char locale_name[] = "";
setlocale( LC_ALL, locale_name );
std::locale::global(std::locale(locale_name));
std::wcin.imbue(std::locale())
std::wcout.imbue(std::locale());
#endif
}
using std::endl;
int main( const int argc, const char * const argv[] )
{
init_locale();
const path cwd = (argc > 1) ? absolute(path( argv[1], std::locale() ))
: absolute(current_path());
if (exists(cwd)) {
std::wcout << cwd.wstring() << endl;
} else {
std::wcerr << "Path does not exist.\n";
return EXIT_FAILURE;
}
if (is_directory(cwd)) {
for ( const directory_entry &f : directory_iterator(cwd) )
std::wcout << f.path().filename().wstring() << endl;
}
return EXIT_SUCCESS;
}
这可能比实际需要的复杂得多：截至 2018 年，
std::filesystem<experimental/filesystem>这是一个简化版本，仅包含使
wcout#include <iostream>
#include <locale>
#include <locale.h>
#ifndef MS_STDLIB_BUGS
# if ( _MSC_VER || __MINGW32__ || __MSVCRT__ )
# define MS_STDLIB_BUGS 1
# else
# define MS_STDLIB_BUGS 0
# endif
#endif
#if MS_STDLIB_BUGS
# include <io.h>
# include <fcntl.h>
#endif
void init_locale(void)
{
#if MS_STDLIB_BUGS
constexpr char cp_utf16le[] = ".1200";
setlocale( LC_ALL, cp_utf16le );
_setmode( _fileno(stdout), _O_WTEXT );
#else
// The correct locale name may vary by OS, e.g., "en_US.utf8".
constexpr char locale_name[] = "";
setlocale( LC_ALL, locale_name );
std::locale::global(std::locale(locale_name));
std::wcin.imbue(std::locale())
std::wcout.imbue(std::locale());
#endif
}
C++ 说：
对相应的宽字符流和窄字符流的混合操作遵循与对[C++11: 27.4.1/3]:混合此类操作相同的语义，如 ISO C 标准修正案 1 中所指定。FILE
并且参考文档说：
流的定义已更改，以包括文本流和二进制流的方向概念。在流与文件关联之后，但在对流执行任何操作之前，流是没有方向的。如果将宽字符输入或输出函数应用于无方向的流，则该流将变为宽方向。同样，如果将字节输入或输出操作应用于具有方向的流，则该流将变为面向字节的。此后，只有
或fwide()函数可以更改流的方向。freopen()字节输入/输出函数不得应用于面向宽的流，宽字符输入/输出函数不得应用于面向字节的流。
根据我的解释，简而言之，不要混合
std::coutstd::wcout这是因为 Unicode 在代码页中无法表示，导致 wcout 失败。
std::wcout<<"abc "<<L'\u240d'<<" defg "<<L'א'<<" hijk"<<std::endl;
if(std::wcout.fail()){
std::cout<<"\nConversion didn't succeed\n";
std::wcout << "This statement has no effect on the console";
std::wcout.clear();
std::wcout<<"hello world from wcout! \n";
}
std::cout<<"hello world from cout! \n";
std::wcout<<"hello world from wcout again! \n";
今天这个问题可以使用标准库函数来解决。
每次转换所需的步骤是刷新最近使用的流并调用 _setmode(_fileno(stdout), _O_XXX) 准备 stdout 接收正确类型的数据。要从 wcout 更改为二进制数据，需要两次调用 _setmode()
同时使用 flush 和 _setmode 的一个原因是，当库需要两字节值时，避免缓冲区中的字节数为奇数而导致崩溃。 （当然，如果您继续使用相同的流，则在进行更改之前无需执行任何操作。）
你可以看出我正在使用 Windows，因为“ “ 被翻译为” “ 除了二进制输出。
#include <iostream>
#include <io.h>
#inlcude <fcntl.h>
int main( )
{
// To start sending to the console in UNICODE/wcout
_setmode(_fileno(stdout), _O_U16TEXT);
std::wcout << "abc " << L'\u240d' << " defg " << L'א' << " hijk" << std::endl;
//then to switch to text/cout
std::wcout.flush();
_setmode(_fileno(stdout), _O_TEXT);
std::cout << "hello world from cout! \n";
// to switch back to wcout
std::cout.flush();
_setmode(_fileno(stdout), _O_U16TEXT);
std::wcout << "hello world from wcout! \n";
// To switch from wcout to binary output: (One reason to use cout
// is that wcout will not accept an odd number of bytes)
std::wcout.flush();
_setmode(_fileno(stdout), _O_TEXT);
_setmode(_fileno(stdout), _O_BINARY);
uint8_t bytes[]{ 8, 0xa0, 0xff, 0x7f, '\n', 0x00, 0x31, 0x5a };
std::cout.write((char*)bytes, sizeof(bytes));
// to switch back to wcout:
std::cout.flush();
_setmode(_fileno(stdout), _O_TEXT);
_setmode(_fileno(stdout), _O_U16TEXT);
std::wcout << "Done" << std::endl;
return 0;
}
通过管道将其通过 od -tcx1 给出
0000000 a \0 b \0 c \0 \0 \r $ \0 d \0 e \0
61 00 62 00 63 00 20 00 0d 24 20 00 64 00 65 00
0000020 f \0 g \0 \0 320 005 \0 h \0 i \0 j \0
66 00 67 00 20 00 d0 05 20 00 68 00 69 00 6a 00
0000040 k \0 \r \0 \n \0 h e l l o w o r l
6b 00 0d 00 0a 00 68 65 6c 6c 6f 20 77 6f 72 6c
0000060 d f r o m c o u t ! \r \n h
64 20 66 72 6f 6d 20 63 6f 75 74 21 20 0d 0a 68
0000100 \0 e \0 l \0 l \0 o \0 \0 w \0 o \0 r
00 65 00 6c 00 6c 00 6f 00 20 00 77 00 6f 00 72
0000120 \0 l \0 d \0 \0 f \0 r \0 o \0 m \0
00 6c 00 64 00 20 00 66 00 72 00 6f 00 6d 00 20
0000140 \0 w \0 c \0 o \0 u \0 t \0 ! \0 \0 \r
00 77 00 63 00 6f 00 75 00 74 00 21 00 20 00 0d
0000160 \0 \n \0 \b 240 377 177 \n \0 1 Z D \0 o \0 n
00 0a 00 08 a0 ff 7f 0a 00 31 5a 44 00 6f 00 6e
0000200 \0 e \0 \r \0 \n \0
00 65 00 0d 00 0a 0
0000207