Re: Need help with COM dll registration at runtime
 
"Suman" <skarpio@gmail.com> wrote in message
news:1173695708.494916.223060@8g2000cwh.googlegroups.com
I have only recently started getting my feet wet with COM and have run
into a couple of issues.
I'd appreciate any help that you provide. My reference will be one
article found at:
http://www.codeproject.com/com/com_in_c1.asp
Realize that the article describes the hardest, most verbose and 
inconvenient way of doing COM. It's great as a studying material, to 
understand what's going on under the hood. But for writing everyday 
code, there are better ways.
(I do know about CLSIDFromString() but somehow
just couldn't get past
converting char [] to OLESTR
MultiByteToWideChar. OLESTR is a typedef for WCHAR*, aka wchar_t* .
Note, I call a function to do register this dll, and uptio this,
things work fine. Actually, the CustomRegister() function
is also taken from the codeproject tutorial. However,
CoGetClassObject() fails saying:
"ClassFactory cannot supply requested class".
Check that the DLL is indeed registered successfully. Check in the 
registry under
HKEY_CLASSES_ROOT\CLSID\{Your CLSID}
In particular, there should be InprocServer32 subkey under this key, 
whose default value contains full path to the DLL.
void GetCLSIDFromFile(const char *path, char *out)
{
   if (out) {
       //*out = 0;
       FILE *fp = fopen(path, "r");
       if (fp) {
           fscanf(fp, "CLSID=%s%*", out);
%* is not a valid format specifier. Does this function succeed? Do you 
get expected CLSID when this function returns?
   CustomRegister(ri);
What does CustomRegister do? It is unusual for the client to register 
the COM object it's about to use. Normally, the COM object is registered 
at installation time.
-- 
With best wishes,
    Igor Tandetnik
With sufficient thrust, pigs fly just fine. However, this is not 
necessarily a good idea. It is hard to be sure where they are going to 
land, and it could be dangerous sitting under them as they fly 
overhead. -- RFC 1925