使用wpritf输出中文

[恋喵大鲤鱼]

为何我的如下代码输出为空？
setlocale(LC_ALL,"chs");
wchar_t wtest[]=L"测试Test";
wprintf(L"%s\n",wtest);

运行环境：Linux，g++ 4.4.6

[赵4老师]

wprintf是不是windows的东东？

[恋喵大鲤鱼]

引用 楼主 K346K346 的回复:

为何我的如下代码输出为空？ setlocale(LC_ALL,"chs"); wchar_t wtest[]=L"测试Test"; wprintf(L"%s\n",wtest); 运行环境：Linux，g++ 4.4.6

wprintf是C标准库函数！

[kongl123]

%ls替换%s。 %s还是按字节去读；sizeof(wchar_t) == 4，“测”的wchar_t内存为4b 6d 0 0，4b(K)，6d(m)，所以打印Km

[恋喵大鲤鱼]

引用 2 楼 K346K346 的回复:

[quote=引用 楼主 K346K346 的回复:] 为何我的如下代码输出为空？ setlocale(LC_ALL,"chs"); wchar_t wtest[]=L"测试Test"; wprintf(L"%s\n",wtest); 运行环境：Linux，g++ 4.4.6

wprintf是C标准库函数！[/quote] 差不多就这个意思。将代码换成如下内容就可以了： setlocale(LC_ALL,"zh_CN.UTF-8"); wchar_t wtest[]=L"0m~K0m~UTest"; printf("%ls\n",wtest); #或者 printf("%S\n",wtest); 这里需要指明的是代码中字符串的编码方式是UTF-8。

[赵4老师]

WPRINTF Section: Linux Programmer's Manual (3 ) Updated: 1999-11-20 -------------------------------------------------------------------------------- NAME wprintf, fwprintf, swprintf, vwprintf, vfwprintf, vswprintf - formatted wide character output conversion SYNOPSIS #include <stdio.h> #include <wchar.h> int wprintf(const wchar_t *format, ...); int fwprintf(FILE *stream, const wchar_t *format, ...); int swprintf(wchar_t *wcs, size_t maxlen, const wchar_t *format, ...); #include <stdarg.h> int vwprintf(const wchar_t *format, va_list args); int vfwprintf(FILE *stream, const wchar_t *format, va_list args); int vswprintf(wchar_t *wcs, size_t maxlen, const wchar_t *format, va_list args); DESCRIPTION The wprintf family of functions is the wide-character equivalent of the printf family of functions. It performs formatted output of wide characters. The wprintf and vwprintf functions perform wide character output to stdout. stdout must not be byte oriented; see function fwide for more information. The fwprintf and vfwprintf functions perform wide character output to stream. stream must not be byte oriented; see function fwide for more information. The swprintf and vswprintf functions perform wide character output to an array of wide characters. The programmer must ensure that there is room for at least maxlen wide characters at wcs. These functions are like the printf, vprintf, fprintf, vfprintf, sprintf, vsprintf functions except for the following differences: * The format string is a wide character string. * The output consists of wide characters, not bytes. * swprintf and vswprintf take a maxlen argument, sprintf and vsprintf do not. (snprintf and vsnprintf take a maxlen argument, but these functions do not return -1 upon buffer overflow on Linux.) The treatment of the conversion characters c and s is different: c If no l modifier is present, the int argument is converted to a wide character by a call to the btowc function, and the resulting wide character is written. If an l modifier is present, the wint_t (wide character) argument is written. s If no l modifier is present: The ``const char *'' argument is expected to be a pointer to an array of character type (pointer to a string) containing a multibyte character sequence beginning in the initial shift state. Characters from the array are converted to wide characters (each by a call to the mbrtowc function with a conversion state starting in the initial state before the first byte). The resulting wide characters are written up to (but not including) the terminating null wide character. If a precision is specified, no more wide characters than the number specified are written. Note that the precision determines the number of wide characters written, not the number of bytes or screen positions. The array must contain a terminating null byte, unless a precision is given and it is so small that the number of converted wide characters reaches it before the end of the array is reached. -- If an l modifier is present: The ``const wchar_t *'' argument is expected to be a pointer to an array of wide characters. Wide characters from the array are written up to (but not including) a terminating null wide character. If a precision is specified, no more than the number specified are written. The array must contain a terminating null wide character, unless a precision is given and it is smaller than or equal to the number of wide characters in the array. RETURN VALUE The functions return the number of wide characters written, excluding the terminating null wide character in case of the functions swprintf and vswprintf. They return -1 when an error occurs. CONFORMING TO ISO/ANSI C, UNIX98 SEE ALSO fprintf(3), fputwc(3), fwide(3), printf(3), snprintf(3), wscanf(3) NOTES The behaviour of wprintf et al. depends on the LC_CTYPE category of the current locale. If the format string contains non-ASCII wide characters, the program will only work correctly if the LC_CTYPE category of the current locale at run time is the same as the LC_CTYPE category of the current locale at compile time. This is because the wchar_t representation is platform and locale dependent. (The GNU libc represents wide characters using their Unicode (ISO-10646) code point, but other platforms don't do this. Also, the use of ISO C99 universal character names of the form \unnnn does not solve this problem.) Therefore, in internationalized programs, the format string should consist of ASCII wide characters only, or should be constructed at run time in an internationalized way (e.g. using gettext or iconv, followed by mbstowcs). --------------------------------------------------------------------------------

[赵4老师]

printf, wprintf Print formatted output to the standard output stream. int printf( const char *format [, argument]... ); int wprintf( const wchar_t *format [, argument]... ); Routine Required Header Compatibility printf <stdio.h> ANSI, Win 95, Win NT wprintf <stdio.h> or <wchar.h> ANSI, Win 95, Win NT For additional compatibility information, see Compatibility in the Introduction. Libraries LIBC.LIB Single thread static library, retail version LIBCMT.LIB Multithread static library, retail version MSVCRT.LIB Import library for MSVCRT.DLL, retail version Return Value Each of these functions returns the number of characters printed, or a negative value if an error occurs. Parameters format Format control argument Optional arguments Remarks The printf function formats and prints a series of characters and values to the standard output stream, stdout. If arguments follow the format string, the format string must contain specifications that determine the output format for the arguments. printf and fprintf behave identically except that printf writes output to stdout rather than to a destination of type FILE. wprintf is a wide-character version of printf; format is a wide-character string. wprintf and printf behave identically otherwise. Generic-Text Routine Mappings TCHAR.H Routine _UNICODE & _MBCS Not Defined _MBCS Defined _UNICODE Defined _tprintf printf printf wprintf The format argument consists of ordinary characters, escape sequences, and (if arguments follow format) format specifications. The ordinary characters and escape sequences are copied to stdout in order of their appearance. For example, the line printf("Line one\n\t\tLine two\n"); produces the output Line one Line two Format specifications always begin with a percent sign (%) and are read left to right. When printf encounters the first format specification (if any), it converts the value of the first argument after format and outputs it accordingly. The second format specification causes the second argument to be converted and output, and so on. If there are more arguments than there are format specifications, the extra arguments are ignored. The results are undefined if there are not enough arguments for all the format specifications. Example /* PRINTF.C: This program uses the printf and wprintf functions * to produce formatted output. */ #include <stdio.h> void main( void ) { char ch = 'h', *string = "computer"; int count = -9234; double fp = 251.7366; wchar_t wch = L'w', *wstring = L"Unicode"; /* Display integers. */ printf( "Integer formats:\n" "\tDecimal: %d Justified: %.6d Unsigned: %u\n", count, count, count, count ); printf( "Decimal %d as:\n\tHex: %Xh C hex: 0x%x Octal: %o\n", count, count, count, count ); /* Display in different radixes. */ printf( "Digits 10 equal:\n\tHex: %i Octal: %i Decimal: %i\n", 0x10, 010, 10 ); /* Display characters. */ printf("Characters in field (1):\n%10c%5hc%5C%5lc\n", ch, ch, wch, wch); wprintf(L"Characters in field (2):\n%10C%5hc%5c%5lc\n", ch, ch, wch, wch); /* Display strings. */ printf("Strings in field (1):\n%25s\n%25.4hs\n\t%S%25.3ls\n", string, string, wstring, wstring); wprintf(L"Strings in field (2):\n%25S\n%25.4hs\n\t%s%25.3ls\n", string, string, wstring, wstring); /* Display real numbers. */ printf( "Real numbers:\n\t%f %.2f %e %E\n", fp, fp, fp, fp ); /* Display pointer. */ printf( "\nAddress as:\t%p\n", &count); /* Count characters printed. */ printf( "\nDisplay to here:\n" ); printf( "1234567890123456%n78901234567890\n", &count ); printf( "\tNumber displayed: %d\n\n", count ); } Output Integer formats: Decimal: -9234 Justified: -009234 Unsigned: 4294958062 Decimal -9234 as: Hex: FFFFDBEEh C hex: 0xffffdbee Octal: 37777755756 Digits 10 equal: Hex: 16 Octal: 8 Decimal: 10 Characters in field (1): h h w w Characters in field (2): h h w w Strings in field (1): computer comp Unicode Uni Strings in field (2): computer comp Unicode Uni Real numbers: 251.736600 251.74 2.517366e+002 2.517366E+002 Address as: 0012FFAC Display to here: 123456789012345678901234567890 Number displayed: 16 Floating-Point Support Routines | Stream I/O Routines | Locale Routines See Also fopen, fprintf, scanf, sprintf, vprintf Functions s String When used with printf functions, specifies a single-byte–character string; when used with wprintf functions, specifies a wide-character string. Characters are printed up to the first null character or until the precision value is reached. S String When used with printf functions, specifies a wide-character string; when used with wprintf functions, specifies a single-byte–character string. Characters are printed up to the first null character or until the precision value is reached.

[赵4老师]

可惜windows下和linux下的wprintf不完全兼容。