string和wstring的互转

方式一：调用Windows API

   
   
#include <Windows.h>
//将string转换成wstring
wstring string2wstring(string str)
{
wstring result;
//获取缓冲区大小，并申请空间，缓冲区大小按字符计算
int len = MultiByteToWideChar(CP_ACP, 0, str.c_str(), str.size(), NULL, 0);
TCHAR* buffer = new TCHAR[len + 1];
//多字节编码转换成宽字节编码
MultiByteToWideChar(CP_ACP, 0, str.c_str(), str.size(), buffer, len);
buffer[len] = '\0'; //添加字符串结尾
//删除缓冲区并返回值
result.append(buffer);
delete[] buffer;
return result;
}

//将wstring转换成string
string wstring2string(wstring wstr)
{
string result;
//获取缓冲区大小，并申请空间，缓冲区大小事按字节计算的
int len = WideCharToMultiByte(CP_ACP, 0, wstr.c_str(), wstr.size(), NULL, 0, NULL, NULL);
char* buffer = new char[len + 1];
//宽字节编码转换成多字节编码
WideCharToMultiByte(CP_ACP, 0, wstr.c_str(), wstr.size(), buffer, len, NULL, NULL);
buffer[len] = '\0';
//删除缓冲区并返回值
result.append(buffer);
delete[] buffer;
return result;
}
   
   

方式二：采用ATL封装_bstr_t的过渡

   
   
#include <comutil.h>
#pragma comment(lib, "comsuppw.lib")

string ws2s(const wstring& ws)
{
    _bstr_t t = ws.c_str();
    char* pchar = ( char*)t;
    string result = pchar;
    return result;
}

wstring s2ws(const string& s)
{
    _bstr_t t = s.c_str();
    wchar_t* pwchar = ( wchar_t*)t;
    wstring result = pwchar;
    return result;
}