C++ wchar_t char wstring string 转换

1.wchart_t转wstring

wchar_t tmpRuleStr[10] = {0};
wstring m_tmpRuleStr = wstring(tmpRuleStr);

2.wstring转wchar_t

wstring str = "123";
wchar_t* tmp = wstr.c_str();

3.string转wstring

std::wstring UTF8ToUnicode(const std::string& utf) 
{
    wchar_t *buff = new wchar_t[utf.length()+1];
    int len = ::MultiByteToWideChar(CP_UTF8, 0, utf.c_str(), (int)utf.length(), buff, (int)utf.length()+1);
    std::wstring str(buff, len);
    delete [] buff;
    return str;
}
std::wstring AnsiToUnicode(const std::string& str) 
{
    wchar_t *buff = new wchar_t[str.length()+1];
    int len = ::MultiByteToWideChar(CP_ACP, 0, str.c_str(), str.length(), buff, str.length()+1);
    std::wstring text(buff, len);
    delete [] buff;
    return text;
}

4.wstring转string

    std::string UnicodeToUTF8(const std::wstring& str) 
    {
        char* buff; 
        int buffersize = ::WideCharToMultiByte(CP_UTF8, 0, str.c_str(), (int)str.length(), 0, 0, 0, 0);
        buff = new char[buffersize+1];
        int len = ::WideCharToMultiByte(CP_UTF8, 0, str.c_str(), (int)str.length(), buff, buffersize+1, 0, 0);
        std::string utf(buff, len);
        delete []buff; 
        return utf;
    }

    std::string UnicodeToAnsi(const std::wstring& str) 
    {
        char *buff; 
        int buffersize = ::WideCharToMultiByte(CP_ACP, 0, str.c_str(), str.length(), 0, 0, NULL, NULL); 
        buff = new char[buffersize+1];
        int len = ::WideCharToMultiByte(CP_ACP, 0, str.c_str(), str.length(), buff, buffersize + 1, NULL, NULL); 
        std::string text(buff, len);
        delete [] buff;
        return text;
    }