|
Hi,
Can I call COM object from device driver (from kernel mode)?
I would like to do is to load up COM, so I can hook it up later.
Thanks
BD
|
|
|
|
|
I am preparing a dialog based application in VC++(MFC).In that I want to prepare a report based on some sql query.I am trying to use "msdbrptr.dll"
and "msdbrpt.dll" and "msde.dll".
Now when I try this code
_DataReportPtr pDr(__uuidof(_DataReport))
It throws an exception "class not registered" .Send me the sample code explaining how to print a report(data report)using mfc.
if there is any other way to prepare a report (with print option) then please let me know.
I don't want to use crystal reports.
|
|
|
|
|
Hi,
I am adding function to DCOM Clients and Servers. Ammending previously written code, so i have little knowledge of the technical details of DCOM.
What I wish to do is return a series of records, 3 strings to be precise.
I was thinking of having one function to return a block of Record Keys. And then having one function to get individual records. Is there are any better ways of doing this?
Cheers
Rich
|
|
|
|
|
Hi,
I have an ATL interface (IOLEDBConnectionPool) for which I want to expose a function
(Initialize) with a DBPROPSET (an OLEDB propertyset struct) but the MIDL compiler doesn't
recognize the DBPROPSET. If I use another variable-type and compile and then change the corresponding
.c and .h files afterwards it works just fine but it is not a nice solution so what can I do to make
the .IDL file compile (see extract from .IDL-file below)?
import "oaidl.idl";
import "ocidl.idl";
[
object,
uuid(D5602000-F5DA-45A0-9A14-066B0D23AAE1),
helpstring("IOLEDBConnectionPool Interface"),
pointer_default(unique)
]
interface IOLEDBConnectionPool : IUnknown
{
[helpstring("method Initialize")] HRESULT Initialize([in] DBPROPSET *pPropSet);
};
....
Johannes
|
|
|
|
|
There are two ways you can get around this. One, add the definition of the DBPROPSET struct to your IDL so it know what you mean. This will work if the clients are C++, VB, VBScript and the like won't. Two, since the param you are passing is a pointer just use a LONG and convert in into a DBPROPSET* when you get it. This would be the prefered method.
|
|
|
|
|
Hi
I need to pass many variables from a client written in VB to a COM server written in VC++. My idea is to modify them by reference in the server. Is there any way to send a structure or a class, containing my variables? The types are int string and bool. Tips or links to articles/examples would be greate.
thanks
|
|
|
|
|
Can i open an ADE file with CDataSource to check it's status. Have tried various provider strings etc.
any ideas
Robbie G
|
|
|
|
|
I have built an activex control that I need to sign and package for network (&internet) delivery. MSDN make references to cabarc.exe and a Cabinet SDK as beening the only way to make cabinet files yet does not provide them on VC++6.0 only on VC++ 5.0 CD set. Is there a new way to make cab files that MSDN eludes to tell me about? Where on Microsoft site can I download cabarc.exe? I am lost!
Many Thanks
Gary,
|
|
|
|
|
|
Thanks Mike,
I spent a few hours yesterday chasing my tail on the MSDN site. A fellow developer suggested searching www.download.com (cnet site). There were a few CAB utilities there that seemed to do the trick so I am out of deep water for now! (Freeware/Shareware once again does the trick... many thanks to all producers of such software)
Gary.
|
|
|
|
|
hi
anybody has any code to drag and drop a url/link from
a IE control. the code would be in c++ and com api.
thanks.
From
Am4000
|
|
|
|
|
Can anyone tell me how to compile the proxy DLL for an .exe COM server which has interface functions that take a BSTR parameter. The VC 6.0 compiler says the proxy requires at least NT 4 to run. This server should run on 9x, NT 4/5
|
|
|
|
|
I try to create an automation interface to my application, and I run into a problem. I have an application root that is creatable, but to create input for other objects in the automation model I need to CoCreate other objects as well. The problem is that new instances of my exe-file is created when I try to create these other objects. I want them to be created from the running instance, not that another instance is created for each CoCreateInstance. How should I do this?
Pål
|
|
|
|
|
Sounds like you are descripbing aggregation/containment. Try something like this.
// Header
CMyObj1 m_Obj1;
CMyObj2 m_Obj2;
// CPP
OnFinalConstruct
{
CoCreateInstance(MyObj1);
CoCreateInstance(MyObj2);
}
|
|
|
|
|
I think I was a bit unclear about the problem description. The object model in for instance Excel has several coclasses (Application, Sheet, Chart etc) I obviously do something wrong, because creating my coclasses from VB result in a new instance of the exe for each coclass. What mechanism ensures that the creatable objects are created in the same instance? Does anyone know?
Pål
|
|
|
|
|
hello.
i'm stuck with an issue that it is easy to write in an MFC app but because i HAVE to use ATL it makes life VERY difficult. I have to rewrite the following procedure from VB into VC++.
The VB program does this:
- checks to see if a particular database is open
- if it is get the application object and run a sub in it (through COM)
- if not then set a registry key and open the database
I can do the last thing easily but check and getting the actual object (as an IDispatch pointer) is the part I'm having trouble with.
Any ideas?
Rob Grundel
|
|
|
|
|
Checking to see if the db is open is a simple task with ATL and OLE DB. If you create an ATL project and insert a database consumer the wizard will walk you through connecting to it. Once you have this should have access to everything you need. The VB project probably uses ADO, which sit on top of OLE DB. See where this is going...
|
|
|
|
|
Hello
use oledb template like CDataSource to check the database
status. you have to include atldbcli.h.
From
Amitava Banerjee
|
|
|
|
|
When I right-click the interface and choose "New Method" in the method creation dialog the return type field is disabled. But I need to create method that returns "short". How do I do that?
|
|
|
|
|
Interface function already return a HRESULT, and your owner return value must be defined in the last argument with [out,retval], example:
myFunction([in] long id, [out,retval] long* pNumber)
By the way, you must not use "short" type , instead using "long".
|
|
|
|
|
What's the difference between COM and OLE?
|
|
|
|
|
A couple of years.
What we refer to as COM today was called OLE a few years ago. Just about every book dealing with COM has a chapter explaining the origins.
|
|
|
|
|
What's the difference between Interface and dispInterface?
|
|
|
|
|
A dispatch interface is usually used by late bound languages such as VB or JavaScript to call, or invoke, methods on your object.
|
|
|
|
|
as mentioned in the above comment the difference is the late binding but the actual differnce is under the hood in the depths of the COM architecture. Dispinterface are just IDispacth Interfaces and don't rely on v-tables. Custom interfaces (non-IDispatch) use vtables and are much faster than IDispatch interfaces. But alas VB has no support (or had no support... i hear the latest release does) for v-table driven interfaces.
Hope this helps some.
Joseph Dempsey
jdempsey@cox.rr.com
Joseph.Dempsey@thermobio.com
"Software Engineering is a race between the programmers, trying to make bigger and better fool-proof software, and the universe trying to make bigger fools. So far the Universe in winning."
--anonymous
|
|
|
|
General 
News 
Suggestion 
Question 
Bug 
Answer 
Joke 
Praise 
Rant 
Admin 
Submit an article or tip
