utf8，anscii与unicode之间的转化

//返回的指针需要自己删除
wchar_t*  ANSIToUnicode( const char* str )
{
    int  len = 0;
    len = strlen(str);
    int  unicodeLen = ::MultiByteToWideChar( CP_ACP,0,str,-1,NULL,0 );  
    wchar_t *  pUnicode;  
    pUnicode = new  wchar_t[unicodeLen+1];  
    memset(pUnicode,0,(unicodeLen+1)*sizeof(wchar_t));  
    ::MultiByteToWideChar( CP_ACP,0, str, -1, (LPWSTR)pUnicode, unicodeLen );  

    return  pUnicode;  
}

char* UncodeToANSI( wchar_t* str )
{
    if ( !str )
    {
        return NULL;
    }

    char*     pElementText;
    int       iTextLen;

    // wide char to multi char
    iTextLen = WideCharToMultiByte( CP_ACP,    0, str, -1, NULL, 0, NULL, NULL );

    pElementText = new char[iTextLen + 1];
    memset( pElementText, 0,  iTextLen + 1);

    ::WideCharToMultiByte( CP_ACP, 0, str, -1, pElementText, iTextLen, NULL, NULL );

    return pElementText;
}

wchar_t* UTF8ToUnicode( const char* str )
{
    int  len = 0;
    len = strlen( str );

    int  unicodeLen = ::MultiByteToWideChar( CP_UTF8, 0, str, -1, NULL, 0 );  

    wchar_t *  pUnicode;  
    pUnicode = new  wchar_t[ unicodeLen + 1 ];  
    memset( pUnicode, 0, (unicodeLen + 1 ) * 2 );  

    ::MultiByteToWideChar( CP_UTF8,0,str,-1,(LPWSTR)pUnicode,unicodeLen );  

    return  pUnicode;  
}

char* UnicodeToUTF8( const wchar_t* str )
{
    char*     pElementText;
    int    iTextLen;

    // wide char to multi char
    iTextLen = WideCharToMultiByte( CP_UTF8, 0, str, -1, NULL, 0, NULL, NULL );

    pElementText = new char[iTextLen + 1];
    memset( ( void* )pElementText, 0, sizeof( char ) * ( iTextLen + 1 ) );

    ::WideCharToMultiByte( CP_UTF8, 0, str, -1,pElementText, iTextLen, NULL, NULL );
    return pElementText;
}