c++ string 和wstring 之间的互相转换函数

#include <string>
std::string ws2s(const std::wstring& ws)
{
    std::string curLocale = setlocale(LC_ALL, NULL);        // curLocale = "C";
    setlocale(LC_ALL, "chs");
    const wchar_t* _Source = ws.c_str();
    size_t _Dsize = 2 * ws.size() + 1;
    char *_Dest = new char[_Dsize];
    memset(_Dest,0,_Dsize);
    wcstombs(_Dest,_Source,_Dsize);
    std::string result = _Dest;
    delete []_Dest;
    setlocale(LC_ALL, curLocale.c_str());
    return result;
}

std::wstring s2ws(const std::string& s)
{
    setlocale(LC_ALL, "chs"); 
    const char* _Source = s.c_str();
    size_t _Dsize = s.size() + 1;
    wchar_t *_Dest = new wchar_t[_Dsize];
    wmemset(_Dest, 0, _Dsize);
    mbstowcs(_Dest,_Source,_Dsize);
    std::wstring result = _Dest;
    delete []_Dest;
    setlocale(LC_ALL, "C");
    return result;
}

BOOL StringToWString(const std::string &str,std::wstring &wstr)
 {    
     int nLen = (int)str.length();    
     wstr.resize(nLen,L' ');
 
     int nResult = MultiByteToWideChar(CP_ACP,0,(LPCSTR)str.c_str(),nLen,(LPWSTR)wstr.c_str(),nLen);
 
     if (nResult == 0)
     {
         return FALSE;
     }
 
     return TRUE;
 }
 //wstring高字节不为0，返回FALSE
 BOOL WStringToString(const std::wstring &wstr,std::string &str)
 {    
     int nLen = (int)wstr.length();    
     str.resize(nLen,' ');
 
     int nResult = WideCharToMultiByte(CP_ACP,0,(LPCWSTR)wstr.c_str(),nLen,(LPSTR)str.c_str(),nLen,NULL,NULL);
 
     if (nResult == 0)
     {
         return FALSE;
     }
 
     return TRUE;
 }

std::wstring StringToWString(const std::string &str)
 {
     std::wstring wstr(str.length(),L' ');
     std::copy(str.begin(), str.end(), wstr.begin());
     return wstr; 
 }
 
 //只拷贝低字节至string中
 std::string WStringToString(const std::wstring &wstr)
 {
     std::string str(wstr.length(), ' ');
     std::copy(wstr.begin(), wstr.end(), str.begin());
     return str; 
 }