mbstowcs和wcstombs函数 ？

[aeolus_boy]

  7 int main(int argc,char** argv){
  8     std::string str = "qilov我e爱你中国";
  9     wchar_t w_char[10000];
 10 
 11     setlocale(LC_ALL,"zh_CN.utf8");
 12     mbstowcs(w_char,str.c_str(),str.size());
 13     std::wstring w_str(w_char);
 14 
 15     //w_str.erase(w_str.begin()+8,w_str.end());
 16 
 17     std::wcout<< w_str.size() <<std::endl;
 18     std::wcout<< w_str <<std::endl;
 19 
 20     wcstombs(&str[0],w_str.c_str(),w_str.size() * 3);
 21 
 22     std::cout << str <<std::endl;
 23 
 24     return EXIT_SUCCESS;
 25 }

运行结果：

11
qilov我e爱你中国
mbstowcs能成功！但再转换回去wcstombs就不行了!
20行和22行没效果！唉，我都疲倦了！

[aeolus_boy]

深夜了，你们都睡了。我还在弄的！始终不能输出

[dengsf]

setlocale 确定已调用成功？

另外，控制台输出也有编码问题的，
试试输出到文件，或断点调试查看内存值，看wcstombs是否能正确转换。

[龙哥依旧]

#include <stdlib.h>
#include <stdio.h>

void main( void )
{
    int i;
    char    *pmbnull  = NULL;
    char    *pmbhello = (char *)malloc( MB_CUR_MAX );
    wchar_t *pwchello = L"Hi";
    wchar_t *pwc      = (wchar_t *)malloc( sizeof( wchar_t ));

    printf( "Convert to multibyte string:\n" );
    i = wcstombs( pmbhello, pwchello, MB_CUR_MAX );
    printf( "\tCharacters converted: %u\n", i );
    printf( "\tHex value of first" );
    printf( " multibyte character: %#.4x\n\n", pmbhello );

    printf( "Convert back to wide-character string:\n" );
    i = mbstowcs( pwc, pmbhello, MB_CUR_MAX );
    printf( "\tCharacters converted: %u\n", i );
    printf( "\tHex value of first" );
    printf( " wide character: %#.4x\n\n", pwc );
}

[龙哥依旧]

#include <stdio.h>
#include <stdlib.h>

void main( void )
{
   int      i;
   char    *pmbbuf   = (char *)malloc( MB_CUR_MAX );
   wchar_t *pwchello = L"Hello, world.";

   printf( "Convert wide-character string:\n" );
   i = wcstombs( pmbbuf, pwchello, MB_CUR_MAX );
   printf( "\tCharacters converted: %u\n", i );
   printf( "\tMultibyte character: %s\n\n", pmbbuf );
}

[luciferisnotsatan]

wchar_t w_char[10000] = {0};
初始化下

[luciferisnotsatan]

mbstowcs(w_char,str.c_str(),str.size()+1);
或者size加上1，size不包含最后的结束符 \0。因此你的代码之转换了字符串，但把最后的 \0 漏了。

[aeolus_boy]

 18     std::wcout<< w_str <<std::endl
22     std::cout << str <<std::endl;

这两句有问题