Using Dll's - Solved

[John Messingham]

Hi All,

In order to allow for new reports to be added to an application later I need to be able to call functions within dll's that are not known about at compile time. I am not sure how to link to these dll's at runtime or if this is possible.

All advice welcome.

[John Messingham]

Using Dll's - solved

Hi All,

The phrase I was trying to remember was 'loadlibrary'

[Michael Mattias]

In order to allow for new reports to be added to an application later I need to be able to call functions within dll's that are not known about at compile time.

The Provider Payment Partner (tm) System uses this same method to offer not only updated versions of 'standard' reports, but allows users to install custom reports and still be able to upgrade the standard product.

That I did because when I was a user, I was always upset that when the publisher had an upgrade, we had to pay to 're-tailor' our applications.

It's also used in The EDI Pal(tm) ANSI EDI Viewer-Editor-Printer to allow for the separate purchase of licenses for priced add-ons.

Here I had to do that because some users are in healthcare and others in manufacturing/distribution, and would never order both sets of options.

[Gary Beene]

The approach is also documented in Help, under the topic:

CALL DWORD statement

[Michael Mattias]

Another circumstance in which I use LoadLibrary/CALL DWORD rather than DECLARE is when I am creating/modifiying a function to be stored in a DLL and getting to the point where the new function is to be tested takes a lot of time, eg to go thru a logon screen, do a File/Open, etc.

With dynamic loading you can set up the calling program pretty much at the point where you click the button to make the call.

If you have made an error, you can recompile the DLL without a "destination write error [file in use]" and try again without ending and restarting the EXE.

MCM