Binary Data File

[Xun Hu]

I'd like to pass a binary data file from component to client, can somebody help me how to implement it?

Thanks.

Make a SafeArray with VT_UI1.

[Saurabh Dasgupta]

Hi,
You can add the desired binary file to your COM DLL as a resource file. This would be similar to adding bitmaps,icons,dialog boxes, etc. But in this case your file is a user defined resource type. Let us say "MyBINARY" . Once you have done this
you can dump the bytes of this data file at run time, and store it as a file or pass it as an array of charcters to some other function.

To get a pointer to a resource data do the following:

/////////////////////////////////////////////////////////////////////////////
HRSRC rc = FindResource(hDllInst,lpszResName,lpszResType);
//here lpszResName is the name you have given to your binary resource,
//eg: "BIN_DATA1"
//lpszResType is the type of resource, "MyBINARY" in this case
//the module instance handle is hDllInst

if (rc == NULL ) return FALSE;

HGLOBAL hglb=LoadResource(NULL,rc);
if (NULL == hglb) return FALSE;

LPVOID lpv=LockResource(hglb);
if (lpv == NULL ) return NULL;
//you have just got hold of the pointer to the first byte of the resource
//Now you need to know the size

DWORD size = SizeofResource(NULL,rc);
/*
Now you have what you want, you can pass the data buffer as an array of bytes along with the size of the array OR dump it to a binary file
*/
/////////////////////////////////////////////////////////////////////////////
Hope this solves your problem,

Regards
Saurabh