linux下Linux下char変換wchar_tローカルutf-8符号化およびwcharの入出力を設定

LInuxでmbstowcs関数を使用すると、charをwchar_に変換できます.t関数の意味:convert a multibyte string to a wide char string説明:The behaviour of mbstowcs depends on the LC_CTYPE category of the current locale戻り値:The mbstowcs()function returns the number of wide characters that make up the converted part of the wide-char-acter string,not including the terminating null wide characters. If an invalid multibyte sequence  was  encountered, (size_t) -1 is returned.
 

 1 #include <string.h>
 2 #include <stdio.h>
 3 #include <stdlib.h>
 4 #include <wchar.h>
 5 #include <locale.h>
 6 #include <iostream>
 7 using namespace std;
10 //  char     wchar13 // locale:       ，mbstowcs       src     
11 int ToWchar(char* &src, wchar_t* &dest, const char *locale = "zh_CN.utf8"){
18   if (src == NULL) {
19     dest = NULL;
20     return 0;
21   }
23   //        locale
24   setlocale(LC_CTYPE, locale);
26   //             
27   int w_size = mbstowcs(NULL, src, 0) + 1;
29   //w_size=0  mbstowcs    -1。              (     locale      )
31   if (w_size == 0) {
32     dest = NULL;
33     return -1;
34   }
36   wcout << "w_size" << w_size << endl;
37   dest = new wchar_t[w_size];
38   if (!dest) return -1;
42   int ret = mbstowcs(dest, src, strlen(src)+1);
43   if (ret <= 0)return -1;46   return 0;
47 }
49 int main(){
51   char* str = "  123";
52   wchar_t *w_str ;
53   ToWchar(str,w_str);
54   wcout << w_str[0] << "--" << w_str[1] << "--" << w_str[2];
55   delete(w_str);
56   return 0;
57 }

 
 

 1 #include <stdio.h>  
 2   
 3 int main(void){  
 5        int       i_number, result;  
 6        float     f_number;  
 7        char      c_number, str[81];  
 8        wchar_t   wc_str, ws_str[81];  
10        printf( "

Enter an int, a float, two chars and two strings
");  
12        result = scanf( "%d %f %c %C %s %S", 
                              &i_number, &f_number, &c_number, &wc_str, str, ws_str );  
13        printf( "
The number of fields input is %d
", 
                               result );  
14        printf( "The contents are: %d %f %c %C %s %S
",
                              i_number, f_number, c_number, wc_str, str, ws_str);  
16        wprintf( L"

Enter an int, a float, two chars and two strings
");  
18        result = wscanf( L"%d %f %hc %lc %S %ls", 
                              &i_number, &f_number, &c_number, &wc_str, str, ws_str );  
19        wprintf( L"
The number of fields input is %d
", 
                               result );  
20        wprintf( L"The contents are: %d %f %C %c %hs %s
",
                               i_number, f_number, c_number, wc_str, str, ws_str);  
21 }