LONG WideCharToMultiByteEx(const CStringW &StrFrom, CStringA &StrTo, UINT PageCode)
{
    if (LONG nBytes = WideCharToMultiByte(PageCode, 0, StrFrom, StrFrom.GetLength(), NULL, 0, NULL, NULL))
    {
        return WideCharToMultiByte(PageCode, 0, StrFrom, StrFrom.GetLength(), StrTo.GetBufferSetLength(nBytes), nBytes, NULL
 
, NULL);
    }
    return 0;
}

LONG MultiByteToWideCharEx(const CStringA &StrFrom, CStringW &StrTo, UINT PageCode)
{
    if (LONG nCount = MultiByteToWideChar(PageCode, 0, StrFrom, StrFrom.GetLength(), NULL, 0))
    {
        return MultiByteToWideChar(PageCode, 0, StrFrom, StrFrom.GetLength(), StrTo.GetBufferSetLength(nCount), nCount);
    }
    return
 
 0;
}

PageCode引數的作用
1.CHAR到WCHAR時表示CHAR的字元編碼是什麼
2.WCHAR到CHAR時表示轉換為什麼樣的字元編碼到CHAR中

我們一般所說的ANSI是GB2312, 中文簡體, PageCode是936