find registered dll on Win98, ME, NT4, 2k, XP

[koko]

My Application is used by a large number of users on computers with different configurations. I am adding an export routine that uses a

DLL and which will be used by only a few of the users. The DLL may or may not be installed on a given PC.

I want to allow the export routine when the DLL is installed on a PC and to disallow it when the DLL is not installed.

My first solution was to add a reference to the DLL using Tools --> References..., and when the application was started, to check

whether the reference was broken or not, and to remove it if broken. This approach did not work - When I tested an .MDB, Access

tried to recompile when opened on a PC without the DLL. When I tested an MDE on a PC without the DLL, it opens without error, but

displays a #Name error on a particular form.

Secondly I tried adding a reference at runtime, but this requires knowing the exact path to the .DLL. I would prefer not to use API calls

as users can be running any version of Windows from 98 to XP which could mean writing different versions of the API calls. Of course, I

will use API calls if there is no other way.

I'm developing for Access 97, Access 2000/2002/2003 and Win98, ME, NT4, 2k, XP

Please suggest the best way to achieve what I need to do.

 

[Douglas J. Steele]

Adding a reference at runtime doesn't actually require the full path to the
DLL: if you know the GUID, you can use the AddFromGUID method. However, you
can't add references to MDEs, so if that's your intent, you're out of luck.

Assuming you do have a reference set, how do you declare an object?

If you've got something like:

Dim objCurr As XXX.YYY

Set objCurr = New XXX.YYY

you can try late binding:

Dim objCurr As Object

Set objCurr = CreateObject("XXX.YYY")

and trap for the error that will arise if the DLL isn't registered. (Error
429: ActiveX component can't create object)


--
Doug Steele, Microsoft Access MVP

(No private e-mails, please)

My Application is used by a large number of users on computers with

different configurations. I am adding an export routine that uses a

DLL and which will be used by only a few of the users. The DLL may or may

not be installed on a given PC.

I want to allow the export routine when the DLL is installed on a PC and

to disallow it when the DLL is not installed.

My first solution was to add a reference to the DLL using Tools -->

References..., and when the application was started, to check

whether the reference was broken or not, and to remove it if broken. This

approach did not work - When I tested an .MDB, Access

tried to recompile when opened on a PC without the DLL. When I tested an

MDE on a PC without the DLL, it opens without error, but

displays a #Name error on a particular form.

Secondly I tried adding a reference at runtime, but this requires knowing

the exact path to the .DLL. I would prefer not to use API calls

as users can be running any version of Windows from 98 to XP which could

mean writing different versions of the API calls. Of course, I