COM

//------------------------//
// Convert BSTR to char * //
//------------------------//
inline char* ConvertBSTRToString(BSTR pSrc)
{
	if(!pSrc) return NULL;
	
	DWORD cb,cwch = ::SysStringLen(pSrc);//convert even embeded NULL
	
	char *szOut = NULL;
	
	if(cb = ::WideCharToMultiByte(CP_ACP, 0, pSrc, cwch + 1, NULL, 0, 0, 0))
	{
		szOut = new char[cb];
		if(szOut)
		{
			szOut[cb - 1]  = '\0';
			
			if(!::WideCharToMultiByte(CP_ACP, 0, pSrc, cwch + 1, szOut, cb, 0, 0))
			{
				delete []szOut;//clean up if failed;
				szOut = NULL;
			}
		}
	}

	return szOut;
};

<br />
_ATL_MIN_CRT and Link Error "unresolved external symbol _main"<br />
--------------------------------------------------------------<br />
<br />
When you build a Release version of an ATL project, you can get the<br />
following link error:<br />
<br />
   LIBCMT.LIB(crt0.obj) : error LNK2001: unresolved external symbol _main<br />
<br />
This error occurs if you are using CRT functions that require CRT startup<br />
code. The Release configurations define _ATL_MIN_CRT, which excludes CRT<br />
startup code from your EXE or DLL. To avoid this error, do one of the<br />
following:<br />
<br />
 - Remove _ATL_MIN_CRT from the list of preprocessor defines to allow CRT<br />
   startup code to be included. On the Build menu, click Settings. Hold<br />
   the ctrl key while selecting all Release configurations. On the C/C++<br />
   tab, choose the General category, then remove _ATL_MIN_CRT from the<br />
   preprocessor definitions edit box.<br />
<br />
 - If possible, remove calls to CRT functions that require CRT startup<br />
   code. Instead, use their Win32 equivalents. For example, use lstrcmp()<br />
   instead of strcmp(). Known functions that require CRT startup code are<br />
   some of the string and floating point functions.<br />

IHTMLElementCollection *pEnum;

pDoc->get_all(&pEnum);
if(pEnum)
{
    ::IHTMLElement *pelem;
                try
                {
        pelem = pEnum->item((long)0);
                }catch(...){};
    if(pelem)
    {
        BSTR wsHTML;
        pelem->get_outerHTML(&wsHTML);
    }
}

STDMETHODIMP CMailslotData::Read(VARIANT *ppResults)
{
   if (!ppResults)
   {
      return E_POINTER;
   }

   return CreateSafeArray(m_pData, m_length, ppResults); 
}

HRESULT CreateSafeArray(
   BYTE *pData,
   DWORD dataLength,
   VARIANT *ppResults)
{
   SAFEARRAYBOUND sab;
   sab.cElements = dataLength;
   sab.lLbound = 0;

   SAFEARRAY *pSa = SafeArrayCreateEx(VT_UI1, 1, &sab, 0);
   
   PVOID pvData;
   
   HRESULT hr = SafeArrayAccessData(pSa, &pvData);
   
   if (SUCCEEDED(hr))
   {
      ::CopyMemory(pvData, pData, dataLength);
   
      hr = ::SafeArrayUnaccessData(pSa);
   }

   if (SUCCEEDED(hr))
   {
      ::VariantInit(ppResults);
           
      (*ppResults).parray = pSa;
      (*ppResults).vt = VT_ARRAY | VT_UI1;
   }

   return hr;
}